Question

If sin A + sin 2 A = x,
cos A + cos 2 A = y then cos A=​

Answer 1

Answer:

this is your answer please give me a like

Answer 2

Step-by-step explanation:

Substituting values

[(sinA+sin2A)2+(cosA+cos2A)2][(sinA+sin2A)2+(cosA+cos2A)2−3]

=[1+1+cosA−cos3A+cos3A+cosA][2+2cosA−3]

=(2+2cosA)(2cosA−1)

=4cosA−2+4cosA−2cosA

=4cos2A+2cosA−2

=2(2cos2A−1)+2cosA

=2cos2A+2cosA

=2(cosA+cos2A)=2y

Hence proved.

How satisfied