Theorem List for Intuitionistic Logic Explorer - 8401-8500   *Has distinct variable
 group(s)
| Type | Label | Description | 
| Statement | 
|   | 
| Theorem | pnpncand 8401 | 
Addition/subtraction cancellation law.  (Contributed by Scott Fenton,
       14-Dec-2017.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)    &   ⊢ (𝜑 → 𝐶 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → ((𝐴 + (𝐵 − 𝐶)) + (𝐶 − 𝐵)) = 𝐴) | 
|   | 
| Theorem | subeqrev 8402 | 
Reverse the order of subtraction in an equality.  (Contributed by Scott
     Fenton, 8-Jul-2013.)
 | 
| ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 − 𝐵) = (𝐶 − 𝐷) ↔ (𝐵 − 𝐴) = (𝐷 − 𝐶))) | 
|   | 
| Theorem | pncan1 8403 | 
Cancellation law for addition and subtraction with 1.  (Contributed by
     Alexander van der Vekens, 3-Oct-2018.)
 | 
| ⊢ (𝐴 ∈ ℂ → ((𝐴 + 1) − 1) = 𝐴) | 
|   | 
| Theorem | npcan1 8404 | 
Cancellation law for subtraction and addition with 1.  (Contributed by
     Alexander van der Vekens, 5-Oct-2018.)
 | 
| ⊢ (𝐴 ∈ ℂ → ((𝐴 − 1) + 1) = 𝐴) | 
|   | 
| Theorem | subeq0bd 8405 | 
If two complex numbers are equal, their difference is zero.  Consequence
       of subeq0ad 8347.  Converse of subeq0d 8345.  Contrapositive of subne0ad 8348.
       (Contributed by David Moews, 28-Feb-2017.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐴 = 𝐵)    ⇒   ⊢ (𝜑 → (𝐴 − 𝐵) = 0) | 
|   | 
| Theorem | renegcld 8406 | 
Closure law for negative of reals.  (Contributed by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℝ)   
 ⇒   ⊢ (𝜑 → -𝐴 ∈ ℝ) | 
|   | 
| Theorem | resubcld 8407 | 
Closure law for subtraction of reals.  (Contributed by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℝ)    &   ⊢ (𝜑 → 𝐵 ∈ ℝ)   
 ⇒   ⊢ (𝜑 → (𝐴 − 𝐵) ∈ ℝ) | 
|   | 
| Theorem | negf1o 8408* | 
Negation is an isomorphism of a subset of the real numbers to the
       negated elements of the subset.  (Contributed by AV, 9-Aug-2020.)
 | 
| ⊢ 𝐹 = (𝑥 ∈ 𝐴 ↦ -𝑥)    ⇒   ⊢ (𝐴 ⊆ ℝ → 𝐹:𝐴–1-1-onto→{𝑛 ∈ ℝ ∣ -𝑛 ∈ 𝐴}) | 
|   | 
| 4.3.3  Multiplication
 | 
|   | 
| Theorem | kcnktkm1cn 8409 | 
k times k minus 1 is a complex number if k is a complex number.
     (Contributed by Alexander van der Vekens, 11-Mar-2018.)
 | 
| ⊢ (𝐾 ∈ ℂ → (𝐾 · (𝐾 − 1)) ∈
 ℂ) | 
|   | 
| Theorem | muladd 8410 | 
Product of two sums.  (Contributed by NM, 14-Jan-2006.)  (Proof shortened
     by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 + 𝐵) · (𝐶 + 𝐷)) = (((𝐴 · 𝐶) + (𝐷 · 𝐵)) + ((𝐴 · 𝐷) + (𝐶 · 𝐵)))) | 
|   | 
| Theorem | subdi 8411 | 
Distribution of multiplication over subtraction.  Theorem I.5 of [Apostol]
     p. 18.  (Contributed by NM, 18-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ) → (𝐴 · (𝐵 − 𝐶)) = ((𝐴 · 𝐵) − (𝐴 · 𝐶))) | 
|   | 
| Theorem | subdir 8412 | 
Distribution of multiplication over subtraction.  Theorem I.5 of [Apostol]
     p. 18.  (Contributed by NM, 30-Dec-2005.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ) → ((𝐴 − 𝐵) · 𝐶) = ((𝐴 · 𝐶) − (𝐵 · 𝐶))) | 
|   | 
| Theorem | mul02 8413 | 
Multiplication by 0.  Theorem I.6 of [Apostol] p. 18.  (Contributed
     by NM, 10-Aug-1999.)
 | 
| ⊢ (𝐴 ∈ ℂ → (0 · 𝐴) = 0) | 
|   | 
| Theorem | mul02lem2 8414 | 
Zero times a real is zero.  Although we prove it as a corollary of
     mul02 8413, the name is for consistency with the
Metamath Proof Explorer
     which proves it before mul02 8413.  (Contributed by Scott Fenton,
     3-Jan-2013.)
 | 
| ⊢ (𝐴 ∈ ℝ → (0 · 𝐴) = 0) | 
|   | 
| Theorem | mul01 8415 | 
Multiplication by 0.  Theorem I.6 of [Apostol] p. 18.  (Contributed
     by NM, 15-May-1999.)  (Revised by Scott Fenton, 3-Jan-2013.)
 | 
| ⊢ (𝐴 ∈ ℂ → (𝐴 · 0) = 0) | 
|   | 
| Theorem | mul02i 8416 | 
Multiplication by 0.  Theorem I.6 of [Apostol]
p. 18.  (Contributed by
       NM, 23-Nov-1994.)
 | 
| ⊢ 𝐴 ∈ ℂ   
 ⇒   ⊢ (0 · 𝐴) = 0 | 
|   | 
| Theorem | mul01i 8417 | 
Multiplication by 0.  Theorem I.6 of [Apostol] p. 18.  (Contributed
       by NM, 23-Nov-1994.)  (Revised by Scott Fenton, 3-Jan-2013.)
 | 
| ⊢ 𝐴 ∈ ℂ   
 ⇒   ⊢ (𝐴 · 0) = 0 | 
|   | 
| Theorem | mul02d 8418 | 
Multiplication by 0.  Theorem I.6 of [Apostol]
p. 18.  (Contributed by
       Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (0 · 𝐴) = 0) | 
|   | 
| Theorem | mul01d 8419 | 
Multiplication by 0.  Theorem I.6 of [Apostol] p. 18.  (Contributed
       by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (𝐴 · 0) = 0) | 
|   | 
| Theorem | ine0 8420 | 
The imaginary unit i is not zero.  (Contributed by NM,
     6-May-1999.)
 | 
| ⊢ i ≠ 0 | 
|   | 
| Theorem | mulneg1 8421 | 
Product with negative is negative of product.  Theorem I.12 of [Apostol]
     p. 18.  (Contributed by NM, 14-May-1999.)  (Proof shortened by Mario
     Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (-𝐴 · 𝐵) = -(𝐴 · 𝐵)) | 
|   | 
| Theorem | mulneg2 8422 | 
The product with a negative is the negative of the product.  (Contributed
     by NM, 30-Jul-2004.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (𝐴 · -𝐵) = -(𝐴 · 𝐵)) | 
|   | 
| Theorem | mulneg12 8423 | 
Swap the negative sign in a product.  (Contributed by NM, 30-Jul-2004.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (-𝐴 · 𝐵) = (𝐴 · -𝐵)) | 
|   | 
| Theorem | mul2neg 8424 | 
Product of two negatives.  Theorem I.12 of [Apostol] p. 18.  (Contributed
     by NM, 30-Jul-2004.)  (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) → (-𝐴 · -𝐵) = (𝐴 · 𝐵)) | 
|   | 
| Theorem | submul2 8425 | 
Convert a subtraction to addition using multiplication by a negative.
     (Contributed by NM, 2-Feb-2007.)
 | 
| ⊢ ((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ) → (𝐴 − (𝐵 · 𝐶)) = (𝐴 + (𝐵 · -𝐶))) | 
|   | 
| Theorem | mulm1 8426 | 
Product with minus one is negative.  (Contributed by NM, 16-Nov-1999.)
 | 
| ⊢ (𝐴 ∈ ℂ → (-1 · 𝐴) = -𝐴) | 
|   | 
| Theorem | mulsub 8427 | 
Product of two differences.  (Contributed by NM, 14-Jan-2006.)
 | 
| ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 − 𝐵) · (𝐶 − 𝐷)) = (((𝐴 · 𝐶) + (𝐷 · 𝐵)) − ((𝐴 · 𝐷) + (𝐶 · 𝐵)))) | 
|   | 
| Theorem | mulsub2 8428 | 
Swap the order of subtraction in a multiplication.  (Contributed by Scott
     Fenton, 24-Jun-2013.)
 | 
| ⊢ (((𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ) ∧ (𝐶 ∈ ℂ ∧ 𝐷 ∈ ℂ)) → ((𝐴 − 𝐵) · (𝐶 − 𝐷)) = ((𝐵 − 𝐴) · (𝐷 − 𝐶))) | 
|   | 
| Theorem | mulm1i 8429 | 
Product with minus one is negative.  (Contributed by NM,
       31-Jul-1999.)
 | 
| ⊢ 𝐴 ∈ ℂ   
 ⇒   ⊢ (-1 · 𝐴) = -𝐴 | 
|   | 
| Theorem | mulneg1i 8430 | 
Product with negative is negative of product.  Theorem I.12 of [Apostol]
       p. 18.  (Contributed by NM, 10-Feb-1995.)  (Revised by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈
 ℂ    ⇒   ⊢ (-𝐴 · 𝐵) = -(𝐴 · 𝐵) | 
|   | 
| Theorem | mulneg2i 8431 | 
Product with negative is negative of product.  (Contributed by NM,
       31-Jul-1999.)  (Revised by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈
 ℂ    ⇒   ⊢ (𝐴 · -𝐵) = -(𝐴 · 𝐵) | 
|   | 
| Theorem | mul2negi 8432 | 
Product of two negatives.  Theorem I.12 of [Apostol] p. 18.
       (Contributed by NM, 14-Feb-1995.)  (Revised by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈
 ℂ    ⇒   ⊢ (-𝐴 · -𝐵) = (𝐴 · 𝐵) | 
|   | 
| Theorem | subdii 8433 | 
Distribution of multiplication over subtraction.  Theorem I.5 of
       [Apostol] p. 18.  (Contributed by NM,
26-Nov-1994.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈ ℂ    &   ⊢ 𝐶 ∈
 ℂ    ⇒   ⊢ (𝐴 · (𝐵 − 𝐶)) = ((𝐴 · 𝐵) − (𝐴 · 𝐶)) | 
|   | 
| Theorem | subdiri 8434 | 
Distribution of multiplication over subtraction.  Theorem I.5 of
       [Apostol] p. 18.  (Contributed by NM,
8-May-1999.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈ ℂ    &   ⊢ 𝐶 ∈
 ℂ    ⇒   ⊢ ((𝐴 − 𝐵) · 𝐶) = ((𝐴 · 𝐶) − (𝐵 · 𝐶)) | 
|   | 
| Theorem | muladdi 8435 | 
Product of two sums.  (Contributed by NM, 17-May-1999.)
 | 
| ⊢ 𝐴 ∈ ℂ    &   ⊢ 𝐵 ∈ ℂ    &   ⊢ 𝐶 ∈ ℂ    &   ⊢ 𝐷 ∈
 ℂ    ⇒   ⊢ ((𝐴 + 𝐵) · (𝐶 + 𝐷)) = (((𝐴 · 𝐶) + (𝐷 · 𝐵)) + ((𝐴 · 𝐷) + (𝐶 · 𝐵))) | 
|   | 
| Theorem | mulm1d 8436 | 
Product with minus one is negative.  (Contributed by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (-1 · 𝐴) = -𝐴) | 
|   | 
| Theorem | mulneg1d 8437 | 
Product with negative is negative of product.  Theorem I.12 of [Apostol]
       p. 18.  (Contributed by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (-𝐴 · 𝐵) = -(𝐴 · 𝐵)) | 
|   | 
| Theorem | mulneg2d 8438 | 
Product with negative is negative of product.  (Contributed by Mario
       Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (𝐴 · -𝐵) = -(𝐴 · 𝐵)) | 
|   | 
| Theorem | mul2negd 8439 | 
Product of two negatives.  Theorem I.12 of [Apostol] p. 18.
       (Contributed by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (-𝐴 · -𝐵) = (𝐴 · 𝐵)) | 
|   | 
| Theorem | subdid 8440 | 
Distribution of multiplication over subtraction.  Theorem I.5 of
       [Apostol] p. 18.  (Contributed by Mario
Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)    &   ⊢ (𝜑 → 𝐶 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (𝐴 · (𝐵 − 𝐶)) = ((𝐴 · 𝐵) − (𝐴 · 𝐶))) | 
|   | 
| Theorem | subdird 8441 | 
Distribution of multiplication over subtraction.  Theorem I.5 of
       [Apostol] p. 18.  (Contributed by Mario
Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)    &   ⊢ (𝜑 → 𝐶 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → ((𝐴 − 𝐵) · 𝐶) = ((𝐴 · 𝐶) − (𝐵 · 𝐶))) | 
|   | 
| Theorem | muladdd 8442 | 
Product of two sums.  (Contributed by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)    &   ⊢ (𝜑 → 𝐶 ∈ ℂ)    &   ⊢ (𝜑 → 𝐷 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → ((𝐴 + 𝐵) · (𝐶 + 𝐷)) = (((𝐴 · 𝐶) + (𝐷 · 𝐵)) + ((𝐴 · 𝐷) + (𝐶 · 𝐵)))) | 
|   | 
| Theorem | mulsubd 8443 | 
Product of two differences.  (Contributed by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)    &   ⊢ (𝜑 → 𝐶 ∈ ℂ)    &   ⊢ (𝜑 → 𝐷 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → ((𝐴 − 𝐵) · (𝐶 − 𝐷)) = (((𝐴 · 𝐶) + (𝐷 · 𝐵)) − ((𝐴 · 𝐷) + (𝐶 · 𝐵)))) | 
|   | 
| Theorem | muls1d 8444 | 
Multiplication by one minus a number.  (Contributed by Scott Fenton,
       23-Dec-2017.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → (𝐴 · (𝐵 − 1)) = ((𝐴 · 𝐵) − 𝐴)) | 
|   | 
| Theorem | mulsubfacd 8445 | 
Multiplication followed by the subtraction of a factor.  (Contributed by
       Alexander van der Vekens, 28-Aug-2018.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℂ)    &   ⊢ (𝜑 → 𝐵 ∈ ℂ)   
 ⇒   ⊢ (𝜑 → ((𝐴 · 𝐵) − 𝐵) = ((𝐴 − 1) · 𝐵)) | 
|   | 
| 4.3.4  Ordering on reals (cont.)
 | 
|   | 
| Theorem | ltadd2 8446 | 
Addition to both sides of 'less than'.  (Contributed by NM,
       12-Nov-1999.)  (Revised by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 < 𝐵 ↔ (𝐶 + 𝐴) < (𝐶 + 𝐵))) | 
|   | 
| Theorem | ltadd2i 8447 | 
Addition to both sides of 'less than'.  (Contributed by NM,
       21-Jan-1997.)
 | 
| ⊢ 𝐴 ∈ ℝ    &   ⊢ 𝐵 ∈ ℝ    &   ⊢ 𝐶 ∈
 ℝ    ⇒   ⊢ (𝐴 < 𝐵 ↔ (𝐶 + 𝐴) < (𝐶 + 𝐵)) | 
|   | 
| Theorem | ltadd2d 8448 | 
Addition to both sides of 'less than'.  (Contributed by Mario Carneiro,
       27-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℝ)    &   ⊢ (𝜑 → 𝐵 ∈ ℝ)    &   ⊢ (𝜑 → 𝐶 ∈ ℝ)   
 ⇒   ⊢ (𝜑 → (𝐴 < 𝐵 ↔ (𝐶 + 𝐴) < (𝐶 + 𝐵))) | 
|   | 
| Theorem | ltadd2dd 8449 | 
Addition to both sides of 'less than'.  (Contributed by Mario
         Carneiro, 30-May-2016.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℝ)    &   ⊢ (𝜑 → 𝐵 ∈ ℝ)    &   ⊢ (𝜑 → 𝐶 ∈ ℝ)    &   ⊢ (𝜑 → 𝐴 < 𝐵)    ⇒   ⊢ (𝜑 → (𝐶 + 𝐴) < (𝐶 + 𝐵)) | 
|   | 
| Theorem | ltletrd 8450 | 
Transitive law deduction for 'less than', 'less than or equal to'.
         (Contributed by NM, 9-Jan-2006.)
 | 
| ⊢ (𝜑 → 𝐴 ∈ ℝ)    &   ⊢ (𝜑 → 𝐵 ∈ ℝ)    &   ⊢ (𝜑 → 𝐶 ∈ ℝ)    &   ⊢ (𝜑 → 𝐴 < 𝐵)   
 &   ⊢ (𝜑 → 𝐵 ≤ 𝐶)    ⇒   ⊢ (𝜑 → 𝐴 < 𝐶) | 
|   | 
| Theorem | ltaddneg 8451 | 
Adding a negative number to another number decreases it.  (Contributed by
     Glauco Siliprandi, 11-Dec-2019.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 0 ↔ (𝐵 + 𝐴) < 𝐵)) | 
|   | 
| Theorem | ltaddnegr 8452 | 
Adding a negative number to another number decreases it.  (Contributed by
     AV, 19-Mar-2021.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 0 ↔ (𝐴 + 𝐵) < 𝐵)) | 
|   | 
| Theorem | lelttrdi 8453 | 
If a number is less than another number, and the other number is less
       than or equal to a third number, the first number is less than the third
       number.  (Contributed by Alexander van der Vekens, 24-Mar-2018.)
 | 
| ⊢ (𝜑 → (𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ))    &   ⊢ (𝜑 → 𝐵 ≤ 𝐶)    ⇒   ⊢ (𝜑 → (𝐴 < 𝐵 → 𝐴 < 𝐶)) | 
|   | 
| Theorem | gt0ne0 8454 | 
Positive implies nonzero.  (Contributed by NM, 3-Oct-1999.)  (Proof
     shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 0 < 𝐴) → 𝐴 ≠ 0) | 
|   | 
| Theorem | lt0ne0 8455 | 
A number which is less than zero is not zero.  See also lt0ap0 8675 which is
     similar but for apartness.  (Contributed by Stefan O'Rear,
     13-Sep-2014.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐴 < 0) → 𝐴 ≠ 0) | 
|   | 
| Theorem | ltadd1 8456 | 
Addition to both sides of 'less than'.  Part of definition 11.2.7(vi) of
     [HoTT], p.  (varies).  (Contributed by NM,
12-Nov-1999.)  (Proof shortened
     by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 < 𝐵 ↔ (𝐴 + 𝐶) < (𝐵 + 𝐶))) | 
|   | 
| Theorem | leadd1 8457 | 
Addition to both sides of 'less than or equal to'.  Part of definition
     11.2.7(vi) of [HoTT], p.  (varies). 
(Contributed by NM, 18-Oct-1999.)
     (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 ≤ 𝐵 ↔ (𝐴 + 𝐶) ≤ (𝐵 + 𝐶))) | 
|   | 
| Theorem | leadd2 8458 | 
Addition to both sides of 'less than or equal to'.  (Contributed by NM,
     26-Oct-1999.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 ≤ 𝐵 ↔ (𝐶 + 𝐴) ≤ (𝐶 + 𝐵))) | 
|   | 
| Theorem | ltsubadd 8459 | 
'Less than' relationship between subtraction and addition.  (Contributed
     by NM, 21-Jan-1997.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) < 𝐶 ↔ 𝐴 < (𝐶 + 𝐵))) | 
|   | 
| Theorem | ltsubadd2 8460 | 
'Less than' relationship between subtraction and addition.  (Contributed
     by NM, 21-Jan-1997.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) < 𝐶 ↔ 𝐴 < (𝐵 + 𝐶))) | 
|   | 
| Theorem | lesubadd 8461 | 
'Less than or equal to' relationship between subtraction and addition.
     (Contributed by NM, 17-Nov-2004.)  (Proof shortened by Mario Carneiro,
     27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) ≤ 𝐶 ↔ 𝐴 ≤ (𝐶 + 𝐵))) | 
|   | 
| Theorem | lesubadd2 8462 | 
'Less than or equal to' relationship between subtraction and addition.
     (Contributed by NM, 10-Aug-1999.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) ≤ 𝐶 ↔ 𝐴 ≤ (𝐵 + 𝐶))) | 
|   | 
| Theorem | ltaddsub 8463 | 
'Less than' relationship between addition and subtraction.  (Contributed
     by NM, 17-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 + 𝐵) < 𝐶 ↔ 𝐴 < (𝐶 − 𝐵))) | 
|   | 
| Theorem | ltaddsub2 8464 | 
'Less than' relationship between addition and subtraction.  (Contributed
     by NM, 17-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 + 𝐵) < 𝐶 ↔ 𝐵 < (𝐶 − 𝐴))) | 
|   | 
| Theorem | leaddsub 8465 | 
'Less than or equal to' relationship between addition and subtraction.
     (Contributed by NM, 6-Apr-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 + 𝐵) ≤ 𝐶 ↔ 𝐴 ≤ (𝐶 − 𝐵))) | 
|   | 
| Theorem | leaddsub2 8466 | 
'Less than or equal to' relationship between and addition and subtraction.
     (Contributed by NM, 6-Apr-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 + 𝐵) ≤ 𝐶 ↔ 𝐵 ≤ (𝐶 − 𝐴))) | 
|   | 
| Theorem | suble 8467 | 
Swap subtrahends in an inequality.  (Contributed by NM, 29-Sep-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) ≤ 𝐶 ↔ (𝐴 − 𝐶) ≤ 𝐵)) | 
|   | 
| Theorem | lesub 8468 | 
Swap subtrahends in an inequality.  (Contributed by NM, 29-Sep-2005.)
     (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 ≤ (𝐵 − 𝐶) ↔ 𝐶 ≤ (𝐵 − 𝐴))) | 
|   | 
| Theorem | ltsub23 8469 | 
'Less than' relationship between subtraction and addition.  (Contributed
     by NM, 4-Oct-1999.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → ((𝐴 − 𝐵) < 𝐶 ↔ (𝐴 − 𝐶) < 𝐵)) | 
|   | 
| Theorem | ltsub13 8470 | 
'Less than' relationship between subtraction and addition.  (Contributed
     by NM, 17-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 < (𝐵 − 𝐶) ↔ 𝐶 < (𝐵 − 𝐴))) | 
|   | 
| Theorem | le2add 8471 | 
Adding both sides of two 'less than or equal to' relations.  (Contributed
     by NM, 17-Apr-2005.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 ≤ 𝐶 ∧ 𝐵 ≤ 𝐷) → (𝐴 + 𝐵) ≤ (𝐶 + 𝐷))) | 
|   | 
| Theorem | lt2add 8472 | 
Adding both sides of two 'less than' relations.  Theorem I.25 of [Apostol]
     p. 20.  (Contributed by NM, 15-Aug-1999.)  (Proof shortened by Mario
     Carneiro, 27-May-2016.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 < 𝐶 ∧ 𝐵 < 𝐷) → (𝐴 + 𝐵) < (𝐶 + 𝐷))) | 
|   | 
| Theorem | ltleadd 8473 | 
Adding both sides of two orderings.  (Contributed by NM, 23-Dec-2007.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 < 𝐶 ∧ 𝐵 ≤ 𝐷) → (𝐴 + 𝐵) < (𝐶 + 𝐷))) | 
|   | 
| Theorem | leltadd 8474 | 
Adding both sides of two orderings.  (Contributed by NM, 15-Aug-2008.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 ≤ 𝐶 ∧ 𝐵 < 𝐷) → (𝐴 + 𝐵) < (𝐶 + 𝐷))) | 
|   | 
| Theorem | addgt0 8475 | 
The sum of 2 positive numbers is positive.  (Contributed by NM,
     1-Jun-2005.)  (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (0 < 𝐴 ∧ 0 < 𝐵)) → 0 < (𝐴 + 𝐵)) | 
|   | 
| Theorem | addgegt0 8476 | 
The sum of nonnegative and positive numbers is positive.  (Contributed by
     NM, 28-Dec-2005.)  (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (0 ≤ 𝐴 ∧ 0 < 𝐵)) → 0 < (𝐴 + 𝐵)) | 
|   | 
| Theorem | addgtge0 8477 | 
The sum of nonnegative and positive numbers is positive.  (Contributed by
     NM, 28-Dec-2005.)  (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (0 < 𝐴 ∧ 0 ≤ 𝐵)) → 0 < (𝐴 + 𝐵)) | 
|   | 
| Theorem | addge0 8478 | 
The sum of 2 nonnegative numbers is nonnegative.  (Contributed by NM,
     17-Mar-2005.)  (Proof shortened by Andrew Salmon, 19-Nov-2011.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (0 ≤ 𝐴 ∧ 0 ≤ 𝐵)) → 0 ≤ (𝐴 + 𝐵)) | 
|   | 
| Theorem | ltaddpos 8479 | 
Adding a positive number to another number increases it.  (Contributed by
     NM, 17-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (0 < 𝐴 ↔ 𝐵 < (𝐵 + 𝐴))) | 
|   | 
| Theorem | ltaddpos2 8480 | 
Adding a positive number to another number increases it.  (Contributed by
     NM, 8-Apr-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (0 < 𝐴 ↔ 𝐵 < (𝐴 + 𝐵))) | 
|   | 
| Theorem | ltsubpos 8481 | 
Subtracting a positive number from another number decreases it.
     (Contributed by NM, 17-Nov-2004.)  (Proof shortened by Andrew Salmon,
     19-Nov-2011.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (0 < 𝐴 ↔ (𝐵 − 𝐴) < 𝐵)) | 
|   | 
| Theorem | posdif 8482 | 
Comparison of two numbers whose difference is positive.  (Contributed by
     NM, 17-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 ↔ 0 < (𝐵 − 𝐴))) | 
|   | 
| Theorem | lesub1 8483 | 
Subtraction from both sides of 'less than or equal to'.  (Contributed by
     NM, 13-May-2004.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 ≤ 𝐵 ↔ (𝐴 − 𝐶) ≤ (𝐵 − 𝐶))) | 
|   | 
| Theorem | lesub2 8484 | 
Subtraction of both sides of 'less than or equal to'.  (Contributed by NM,
     29-Sep-2005.)  (Revised by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 ≤ 𝐵 ↔ (𝐶 − 𝐵) ≤ (𝐶 − 𝐴))) | 
|   | 
| Theorem | ltsub1 8485 | 
Subtraction from both sides of 'less than'.  (Contributed by FL,
     3-Jan-2008.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 < 𝐵 ↔ (𝐴 − 𝐶) < (𝐵 − 𝐶))) | 
|   | 
| Theorem | ltsub2 8486 | 
Subtraction of both sides of 'less than'.  (Contributed by NM,
     29-Sep-2005.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ ∧ 𝐶 ∈ ℝ) → (𝐴 < 𝐵 ↔ (𝐶 − 𝐵) < (𝐶 − 𝐴))) | 
|   | 
| Theorem | lt2sub 8487 | 
Subtracting both sides of two 'less than' relations.  (Contributed by
     Mario Carneiro, 14-Apr-2016.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 < 𝐶 ∧ 𝐷 < 𝐵) → (𝐴 − 𝐵) < (𝐶 − 𝐷))) | 
|   | 
| Theorem | le2sub 8488 | 
Subtracting both sides of two 'less than or equal to' relations.
     (Contributed by Mario Carneiro, 14-Apr-2016.)
 | 
| ⊢ (((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) ∧ (𝐶 ∈ ℝ ∧ 𝐷 ∈ ℝ)) → ((𝐴 ≤ 𝐶 ∧ 𝐷 ≤ 𝐵) → (𝐴 − 𝐵) ≤ (𝐶 − 𝐷))) | 
|   | 
| Theorem | ltneg 8489 | 
Negative of both sides of 'less than'.  Theorem I.23 of [Apostol] p. 20.
     (Contributed by NM, 27-Aug-1999.)  (Proof shortened by Mario Carneiro,
     27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < 𝐵 ↔ -𝐵 < -𝐴)) | 
|   | 
| Theorem | ltnegcon1 8490 | 
Contraposition of negative in 'less than'.  (Contributed by NM,
     8-Nov-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (-𝐴 < 𝐵 ↔ -𝐵 < 𝐴)) | 
|   | 
| Theorem | ltnegcon2 8491 | 
Contraposition of negative in 'less than'.  (Contributed by Mario
     Carneiro, 25-Feb-2015.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 < -𝐵 ↔ 𝐵 < -𝐴)) | 
|   | 
| Theorem | leneg 8492 | 
Negative of both sides of 'less than or equal to'.  (Contributed by NM,
     12-Sep-1999.)  (Proof shortened by Mario Carneiro, 27-May-2016.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 ≤ 𝐵 ↔ -𝐵 ≤ -𝐴)) | 
|   | 
| Theorem | lenegcon1 8493 | 
Contraposition of negative in 'less than or equal to'.  (Contributed by
     NM, 10-May-2004.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (-𝐴 ≤ 𝐵 ↔ -𝐵 ≤ 𝐴)) | 
|   | 
| Theorem | lenegcon2 8494 | 
Contraposition of negative in 'less than or equal to'.  (Contributed by
     NM, 8-Oct-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (𝐴 ≤ -𝐵 ↔ 𝐵 ≤ -𝐴)) | 
|   | 
| Theorem | lt0neg1 8495 | 
Comparison of a number and its negative to zero.  Theorem I.23 of
     [Apostol] p. 20.  (Contributed by NM,
14-May-1999.)
 | 
| ⊢ (𝐴 ∈ ℝ → (𝐴 < 0 ↔ 0 < -𝐴)) | 
|   | 
| Theorem | lt0neg2 8496 | 
Comparison of a number and its negative to zero.  (Contributed by NM,
     10-May-2004.)
 | 
| ⊢ (𝐴 ∈ ℝ → (0 < 𝐴 ↔ -𝐴 < 0)) | 
|   | 
| Theorem | le0neg1 8497 | 
Comparison of a number and its negative to zero.  (Contributed by NM,
     10-May-2004.)
 | 
| ⊢ (𝐴 ∈ ℝ → (𝐴 ≤ 0 ↔ 0 ≤ -𝐴)) | 
|   | 
| Theorem | le0neg2 8498 | 
Comparison of a number and its negative to zero.  (Contributed by NM,
     24-Aug-1999.)
 | 
| ⊢ (𝐴 ∈ ℝ → (0 ≤ 𝐴 ↔ -𝐴 ≤ 0)) | 
|   | 
| Theorem | addge01 8499 | 
A number is less than or equal to itself plus a nonnegative number.
     (Contributed by NM, 21-Feb-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (0 ≤ 𝐵 ↔ 𝐴 ≤ (𝐴 + 𝐵))) | 
|   | 
| Theorem | addge02 8500 | 
A number is less than or equal to itself plus a nonnegative number.
     (Contributed by NM, 27-Jul-2005.)
 | 
| ⊢ ((𝐴 ∈ ℝ ∧ 𝐵 ∈ ℝ) → (0 ≤ 𝐵 ↔ 𝐴 ≤ (𝐵 + 𝐴))) |