Answer:
Explanation:
cot(theta) = cos(theta)/sin(theta)
sec(theta) = 1/ cos(theta)
sin(theta) * (cos(theta) ) / sin(theta) ) * 1/cos(theta)
The sin(theta)s and the cos(theta)s are on opposite sides of the division sign. So you are left with a bunch of ones.
The identity is proved.