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Theorem cscval 47783
Description: Value of the cosecant function. (Contributed by David A. Wheeler, 14-Mar-2014.)
Assertion
Ref Expression
cscval ((𝐴 ∈ β„‚ ∧ (sinβ€˜π΄) β‰  0) β†’ (cscβ€˜π΄) = (1 / (sinβ€˜π΄)))

Proof of Theorem cscval
Dummy variables π‘₯ 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fveq2 6891 . . . 4 (𝑦 = 𝐴 β†’ (sinβ€˜π‘¦) = (sinβ€˜π΄))
21neeq1d 3000 . . 3 (𝑦 = 𝐴 β†’ ((sinβ€˜π‘¦) β‰  0 ↔ (sinβ€˜π΄) β‰  0))
32elrab 3683 . 2 (𝐴 ∈ {𝑦 ∈ β„‚ ∣ (sinβ€˜π‘¦) β‰  0} ↔ (𝐴 ∈ β„‚ ∧ (sinβ€˜π΄) β‰  0))
4 fveq2 6891 . . . 4 (π‘₯ = 𝐴 β†’ (sinβ€˜π‘₯) = (sinβ€˜π΄))
54oveq2d 7424 . . 3 (π‘₯ = 𝐴 β†’ (1 / (sinβ€˜π‘₯)) = (1 / (sinβ€˜π΄)))
6 df-csc 47780 . . 3 csc = (π‘₯ ∈ {𝑦 ∈ β„‚ ∣ (sinβ€˜π‘¦) β‰  0} ↦ (1 / (sinβ€˜π‘₯)))
7 ovex 7441 . . 3 (1 / (sinβ€˜π΄)) ∈ V
85, 6, 7fvmpt 6998 . 2 (𝐴 ∈ {𝑦 ∈ β„‚ ∣ (sinβ€˜π‘¦) β‰  0} β†’ (cscβ€˜π΄) = (1 / (sinβ€˜π΄)))
93, 8sylbir 234 1 ((𝐴 ∈ β„‚ ∧ (sinβ€˜π΄) β‰  0) β†’ (cscβ€˜π΄) = (1 / (sinβ€˜π΄)))
Colors of variables: wff setvar class
Syntax hints:   β†’ wi 4   ∧ wa 396   = wceq 1541   ∈ wcel 2106   β‰  wne 2940  {crab 3432  β€˜cfv 6543  (class class class)co 7408  β„‚cc 11107  0cc0 11109  1c1 11110   / cdiv 11870  sincsin 16006  cscccsc 47777
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2703  ax-sep 5299  ax-nul 5306  ax-pr 5427
This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2534  df-eu 2563  df-clab 2710  df-cleq 2724  df-clel 2810  df-nfc 2885  df-ne 2941  df-ral 3062  df-rex 3071  df-rab 3433  df-v 3476  df-dif 3951  df-un 3953  df-in 3955  df-ss 3965  df-nul 4323  df-if 4529  df-sn 4629  df-pr 4631  df-op 4635  df-uni 4909  df-br 5149  df-opab 5211  df-mpt 5232  df-id 5574  df-xp 5682  df-rel 5683  df-cnv 5684  df-co 5685  df-dm 5686  df-iota 6495  df-fun 6545  df-fv 6551  df-ov 7411  df-csc 47780
This theorem is referenced by:  csccl  47786  recsccl  47789  reccsc  47792  cotsqcscsq  47797
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