Question

Reduce the first expression to the second 1 – cos2 sin2 ; 1

Answer 1

is that cos^2 or cos(2)

Answer 2

cos^2

Answer 3

use identities for sin^2 and cos^2 to eliminate all trig functions.
this link has the identities you need. http://www.math.com/tables/trig/identities.htm