Question

if sin theta + sin squared theta is equal to 1 then find the value of cos square theta + cos. power 4theta

Answer 1

sinA+sin^2A=1.
sinA= 1-sin^2A.
sinA= cos^2A.
So sin^2A= cos^4A.

Given question expression.
cos^2A+cos^4A.
We'll put the above value in this.
sinA + sin^2A.
=1.
Hope it helps.

Answer 2

we are given that,
 sin^2(theta) + sin(theta) = 1

sinФ = 1-sin^Ф  -------(1)

cos^2(Ф) + cos^4(Ф) = cos^2(Ф) [ 1 + cos^2(Ф)]
                                  = (1- sin^2(Ф) )[ 1 + (1 - sin^2(Ф)]
                                 =  (sin(Ф)) [ 1 + sin(Ф)]
therefore, the answer is 1 ;)