We need to prove that
:
1/sin(x) - sinx/tanx = cosx/
tanx
We will start from the right side and prove the left
side.
==> cos x/
tanx
But we know that tan(x)= sinx /
cosx
We willl
substitute:
==> cosx / (sinx/cosx) = cosx* cosx/
sinx = cos^2 x / sinx
But we know that cos^2 x = 1- sin^2
x
==> (1- sin^2 x) / sinx = 1/sinx - sin^2 x/ sinx =
1/sinx - sinx
==> Then we prove that
cosx/ tanx = 1/sinx - sinx
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