Question

7 sin square theta + 3 cos square theta equal to 4​

Answer 1

Answer:

7sin^2a+3cos^2a=4. here a= theta

7(1-cos^2a)+3cos^2a=4

7-7cos^2a+3cos^2 a=4

7-4cos^2 a = 4

cos a=+/- √3/2

Answer 2

Step-by-step explanation:

7sin^2 theta+3 cos^2 theta=4

=>7sin^2 theta+3(1-sin^2 theta)=4

=>7sin^2theta+3-3sin^2theta=4

=>4sin^2theta=4-3=1

=>sin^2theta=1/4

=>sin theta=1/2=sin30

=>theta=30