Theorem List for Intuitionistic Logic Explorer - 8701-8800 *Has distinct variable
group(s)
| Type | Label | Description |
| Statement |
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| Theorem | gt0ne0 8701 |
Positive implies nonzero. (Contributed by NM, 3-Oct-1999.) (Proof
shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | lt0ne0 8702 |
A number which is less than zero is not zero. See also lt0ap0 8922 which is
similar but for apartness. (Contributed by Stefan O'Rear,
13-Sep-2014.)
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| Theorem | ltadd1 8703 |
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.)
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| Theorem | leadd1 8704 |
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.)
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| Theorem | leadd2 8705 |
Addition to both sides of 'less than or equal to'. (Contributed by NM,
26-Oct-1999.)
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| Theorem | ltsubadd 8706 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 21-Jan-1997.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | ltsubadd2 8707 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 21-Jan-1997.)
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| Theorem | lesubadd 8708 |
'Less than or equal to' relationship between subtraction and addition.
(Contributed by NM, 17-Nov-2004.) (Proof shortened by Mario Carneiro,
27-May-2016.)
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| Theorem | lesubadd2 8709 |
'Less than or equal to' relationship between subtraction and addition.
(Contributed by NM, 10-Aug-1999.)
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| Theorem | ltaddsub 8710 |
'Less than' relationship between addition and subtraction. (Contributed
by NM, 17-Nov-2004.)
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| Theorem | ltaddsub2 8711 |
'Less than' relationship between addition and subtraction. (Contributed
by NM, 17-Nov-2004.)
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| Theorem | leaddsub 8712 |
'Less than or equal to' relationship between addition and subtraction.
(Contributed by NM, 6-Apr-2005.)
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| Theorem | leaddsub2 8713 |
'Less than or equal to' relationship between and addition and subtraction.
(Contributed by NM, 6-Apr-2005.)
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| Theorem | suble 8714 |
Swap subtrahends in an inequality. (Contributed by NM, 29-Sep-2005.)
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| Theorem | lesub 8715 |
Swap subtrahends in an inequality. (Contributed by NM, 29-Sep-2005.)
(Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | ltsub23 8716 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 4-Oct-1999.)
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| Theorem | ltsub13 8717 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 17-Nov-2004.)
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| Theorem | le2add 8718 |
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.)
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| Theorem | lt2add 8719 |
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.)
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| Theorem | ltleadd 8720 |
Adding both sides of two orderings. (Contributed by NM, 23-Dec-2007.)
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| Theorem | leltadd 8721 |
Adding both sides of two orderings. (Contributed by NM, 15-Aug-2008.)
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| Theorem | addgt0 8722 |
The sum of 2 positive numbers is positive. (Contributed by NM,
1-Jun-2005.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | addgegt0 8723 |
The sum of nonnegative and positive numbers is positive. (Contributed by
NM, 28-Dec-2005.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | addgtge0 8724 |
The sum of nonnegative and positive numbers is positive. (Contributed by
NM, 28-Dec-2005.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | addge0 8725 |
The sum of 2 nonnegative numbers is nonnegative. (Contributed by NM,
17-Mar-2005.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | ltaddpos 8726 |
Adding a positive number to another number increases it. (Contributed by
NM, 17-Nov-2004.)
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| Theorem | ltaddpos2 8727 |
Adding a positive number to another number increases it. (Contributed by
NM, 8-Apr-2005.)
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| Theorem | ltsubpos 8728 |
Subtracting a positive number from another number decreases it.
(Contributed by NM, 17-Nov-2004.) (Proof shortened by Andrew Salmon,
19-Nov-2011.)
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| Theorem | posdif 8729 |
Comparison of two numbers whose difference is positive. (Contributed by
NM, 17-Nov-2004.)
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| Theorem | lesub1 8730 |
Subtraction from both sides of 'less than or equal to'. (Contributed by
NM, 13-May-2004.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | lesub2 8731 |
Subtraction of both sides of 'less than or equal to'. (Contributed by NM,
29-Sep-2005.) (Revised by Mario Carneiro, 27-May-2016.)
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| Theorem | ltsub1 8732 |
Subtraction from both sides of 'less than'. (Contributed by FL,
3-Jan-2008.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | ltsub2 8733 |
Subtraction of both sides of 'less than'. (Contributed by NM,
29-Sep-2005.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | lt2sub 8734 |
Subtracting both sides of two 'less than' relations. (Contributed by
Mario Carneiro, 14-Apr-2016.)
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| Theorem | le2sub 8735 |
Subtracting both sides of two 'less than or equal to' relations.
(Contributed by Mario Carneiro, 14-Apr-2016.)
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| Theorem | ltneg 8736 |
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.)
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| Theorem | ltnegcon1 8737 |
Contraposition of negative in 'less than'. (Contributed by NM,
8-Nov-2004.)
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| Theorem | ltnegcon2 8738 |
Contraposition of negative in 'less than'. (Contributed by Mario
Carneiro, 25-Feb-2015.)
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| Theorem | leneg 8739 |
Negative of both sides of 'less than or equal to'. (Contributed by NM,
12-Sep-1999.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | lenegcon1 8740 |
Contraposition of negative in 'less than or equal to'. (Contributed by
NM, 10-May-2004.)
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| Theorem | lenegcon2 8741 |
Contraposition of negative in 'less than or equal to'. (Contributed by
NM, 8-Oct-2005.)
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| Theorem | lt0neg1 8742 |
Comparison of a number and its negative to zero. Theorem I.23 of
[Apostol] p. 20. (Contributed by NM,
14-May-1999.)
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| Theorem | lt0neg2 8743 |
Comparison of a number and its negative to zero. (Contributed by NM,
10-May-2004.)
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| Theorem | le0neg1 8744 |
Comparison of a number and its negative to zero. (Contributed by NM,
10-May-2004.)
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| Theorem | le0neg2 8745 |
Comparison of a number and its negative to zero. (Contributed by NM,
24-Aug-1999.)
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| Theorem | addge01 8746 |
A number is less than or equal to itself plus a nonnegative number.
(Contributed by NM, 21-Feb-2005.)
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| Theorem | addge02 8747 |
A number is less than or equal to itself plus a nonnegative number.
(Contributed by NM, 27-Jul-2005.)
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| Theorem | add20 8748 |
Two nonnegative numbers are zero iff their sum is zero. (Contributed by
Jeff Madsen, 2-Sep-2009.) (Proof shortened by Mario Carneiro,
27-May-2016.)
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| Theorem | subge0 8749 |
Nonnegative subtraction. (Contributed by NM, 14-Mar-2005.) (Proof
shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | suble0 8750 |
Nonpositive subtraction. (Contributed by NM, 20-Mar-2008.) (Proof
shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | leaddle0 8751 |
The sum of a real number and a second real number is less then the real
number iff the second real number is negative. (Contributed by Alexander
van der Vekens, 30-May-2018.)
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| Theorem | subge02 8752 |
Nonnegative subtraction. (Contributed by NM, 27-Jul-2005.)
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| Theorem | lesub0 8753 |
Lemma to show a nonnegative number is zero. (Contributed by NM,
8-Oct-1999.) (Proof shortened by Mario Carneiro, 27-May-2016.)
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| Theorem | mullt0 8754 |
The product of two negative numbers is positive. (Contributed by Jeff
Hankins, 8-Jun-2009.)
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| Theorem | 0le1 8755 |
0 is less than or equal to 1. (Contributed by Mario Carneiro,
29-Apr-2015.)
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| Theorem | ltordlem 8756* |
Lemma for eqord1 8757. (Contributed by Mario Carneiro,
14-Jun-2014.)
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| Theorem | eqord1 8757* |
A strictly increasing real function on a subset of is
one-to-one. (Contributed by Mario Carneiro, 14-Jun-2014.) (Revised
by Jim Kingdon, 20-Dec-2022.)
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| Theorem | eqord2 8758* |
A strictly decreasing real function on a subset of is one-to-one.
(Contributed by Mario Carneiro, 14-Jun-2014.)
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| Theorem | leidi 8759 |
'Less than or equal to' is reflexive. (Contributed by NM,
18-Aug-1999.)
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| Theorem | gt0ne0i 8760 |
Positive means nonzero (useful for ordering theorems involving
division). (Contributed by NM, 16-Sep-1999.)
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| Theorem | gt0ne0ii 8761 |
Positive implies nonzero. (Contributed by NM, 15-May-1999.)
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| Theorem | addgt0i 8762 |
Addition of 2 positive numbers is positive. (Contributed by NM,
16-May-1999.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | addge0i 8763 |
Addition of 2 nonnegative numbers is nonnegative. (Contributed by NM,
28-May-1999.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | addgegt0i 8764 |
Addition of nonnegative and positive numbers is positive. (Contributed
by NM, 25-Sep-1999.) (Revised by Mario Carneiro, 27-May-2016.)
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| Theorem | addgt0ii 8765 |
Addition of 2 positive numbers is positive. (Contributed by NM,
18-May-1999.)
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| Theorem | add20i 8766 |
Two nonnegative numbers are zero iff their sum is zero. (Contributed by
NM, 28-Jul-1999.)
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| Theorem | ltnegi 8767 |
Negative of both sides of 'less than'. Theorem I.23 of [Apostol] p. 20.
(Contributed by NM, 21-Jan-1997.)
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| Theorem | lenegi 8768 |
Negative of both sides of 'less than or equal to'. (Contributed by NM,
1-Aug-1999.)
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| Theorem | ltnegcon2i 8769 |
Contraposition of negative in 'less than'. (Contributed by NM,
14-May-1999.)
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| Theorem | lesub0i 8770 |
Lemma to show a nonnegative number is zero. (Contributed by NM,
8-Oct-1999.) (Proof shortened by Andrew Salmon, 19-Nov-2011.)
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| Theorem | ltaddposi 8771 |
Adding a positive number to another number increases it. (Contributed
by NM, 25-Aug-1999.)
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| Theorem | posdifi 8772 |
Comparison of two numbers whose difference is positive. (Contributed by
NM, 19-Aug-2001.)
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| Theorem | ltnegcon1i 8773 |
Contraposition of negative in 'less than'. (Contributed by NM,
14-May-1999.)
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| Theorem | lenegcon1i 8774 |
Contraposition of negative in 'less than or equal to'. (Contributed by
NM, 6-Apr-2005.)
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| Theorem | subge0i 8775 |
Nonnegative subtraction. (Contributed by NM, 13-Aug-2000.)
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| Theorem | ltadd1i 8776 |
Addition to both sides of 'less than'. Theorem I.18 of [Apostol] p. 20.
(Contributed by NM, 21-Jan-1997.)
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| Theorem | leadd1i 8777 |
Addition to both sides of 'less than or equal to'. (Contributed by NM,
11-Aug-1999.)
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| Theorem | leadd2i 8778 |
Addition to both sides of 'less than or equal to'. (Contributed by NM,
11-Aug-1999.)
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| Theorem | ltsubaddi 8779 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 21-Jan-1997.) (Proof shortened by Andrew Salmon,
19-Nov-2011.)
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| Theorem | lesubaddi 8780 |
'Less than or equal to' relationship between subtraction and addition.
(Contributed by NM, 30-Sep-1999.) (Proof shortened by Andrew Salmon,
19-Nov-2011.)
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| Theorem | ltsubadd2i 8781 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 21-Jan-1997.)
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| Theorem | lesubadd2i 8782 |
'Less than or equal to' relationship between subtraction and addition.
(Contributed by NM, 3-Aug-1999.)
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| Theorem | ltaddsubi 8783 |
'Less than' relationship between subtraction and addition. (Contributed
by NM, 14-May-1999.)
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| Theorem | lt2addi 8784 |
Adding both side of two inequalities. Theorem I.25 of [Apostol] p. 20.
(Contributed by NM, 14-May-1999.)
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| Theorem | le2addi 8785 |
Adding both side of two inequalities. (Contributed by NM,
16-Sep-1999.)
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| Theorem | gt0ne0d 8786 |
Positive implies nonzero. (Contributed by Mario Carneiro,
27-May-2016.)
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| Theorem | lt0ne0d 8787 |
Something less than zero is not zero. Deduction form. See also
lt0ap0d 8923 which is similar but for apartness.
(Contributed by David
Moews, 28-Feb-2017.)
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| Theorem | leidd 8788 |
'Less than or equal to' is reflexive. (Contributed by Mario Carneiro,
27-May-2016.)
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| Theorem | lt0neg1d 8789 |
Comparison of a number and its negative to zero. Theorem I.23 of
[Apostol] p. 20. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | lt0neg2d 8790 |
Comparison of a number and its negative to zero. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | le0neg1d 8791 |
Comparison of a number and its negative to zero. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | le0neg2d 8792 |
Comparison of a number and its negative to zero. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | addgegt0d 8793 |
Addition of nonnegative and positive numbers is positive.
(Contributed by Mario Carneiro, 27-May-2016.)
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| Theorem | addgtge0d 8794 |
Addition of positive and nonnegative numbers is positive.
(Contributed by Asger C. Ipsen, 12-May-2021.)
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| Theorem | addgt0d 8795 |
Addition of 2 positive numbers is positive. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | addge0d 8796 |
Addition of 2 nonnegative numbers is nonnegative. (Contributed by
Mario Carneiro, 27-May-2016.)
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| Theorem | ltnegd 8797 |
Negative of both sides of 'less than'. Theorem I.23 of [Apostol] p. 20.
(Contributed by Mario Carneiro, 27-May-2016.)
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| Theorem | lenegd 8798 |
Negative of both sides of 'less than or equal to'. (Contributed by
Mario Carneiro, 27-May-2016.)
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| Theorem | ltnegcon1d 8799 |
Contraposition of negative in 'less than'. (Contributed by Mario
Carneiro, 27-May-2016.)
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| Theorem | ltnegcon2d 8800 |
Contraposition of negative in 'less than'. (Contributed by Mario
Carneiro, 27-May-2016.)
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