Answer:
= 4(1+sin2theta)²
Step-by-step explanation:
Given the equations
tantheta -cottheta =a... 1
costheta +sintheta =b .... 2
We are to find 4b^2(2-b^2)
Squaring both sides of equation 2
(costheta +sintheta)^2 = b^2
cos^2theta + 2costheta sintheta + sin^2 theta = b^2
(cos^2theta+ sin^2 theta) + 2costheta sintheta = b^2
1 + 2costheta sintheta = b^2
1 + sin2theta = b^2
substitute
4b^2(2-b^2)
= 4(1+sin2theta)(2-1+sin2theta)
4(1+sin2theta)(1+sin2theta)
= 4(1+sin2theta)²
