Question #6abe5

1 Answer
Oct 25, 2017

Start by writing the LHS as a single fraction, expand and simplify the denominator and then use c^2+s^2=1 to simplify it further.

Explanation:

LHS denominator becomes (1sinθ)(1+sinθ)=(1sin2θ). Using the pythagorean identity, this is cos2θ.
The LHS numerator is (1+sinθ)2(1sinθ)2
=(1+sinθ+1sinθ)(1+sinθ1+sinθ)
=2(2sinθ)
=4sinθ
So LHS is now 4sinθcos2θ=4sinθsec2θ