Patrick B. answered 01/15/20
Math and computer tutor/teacher
sin^2 1 sin^2
-------- * -------- - ------------- = <---- rewritten using only sines and cosines
cos^2 sin^2 cos^2
sin^2 - sin^4
------------------ <--- common denominator
cos^2 sin^2
1 - sin^2
------------ <--- common factor of sin^2 cancels
cos^2
cos^2
------- <---- trig identity sin^2 cos^2 = 1
cos^2
= 1