Question #4acb5

1 Answer
Nov 28, 2017

I'm assuming you want me to prove:

#sinx/(cscx - cotx) = 1 + cosx#

We rewrite in terms of sine and cosine.

#sinx/(1/sinx - cosx/sinx) = 1 + cosx#

#sinx/((1 - cosx)/sinx) = 1 + cosx#

#sin^2x/(1 - cosx) = 1 + cosx#

Now recall that #sin^2x+ cos^2x = 1#:

#(1 - cos^2x)/(1 - cosx) = 1 + cosx#

#((1+ cosx)(1 - cosx))/(1 - cosx) = 1 + cosx#

#1 + cosx = 1 + cosx#

Proved.

Hopefully this helps!