Question

If a cos + b sin = 4 and a sin -b cos =3 ,then 2 + b2 is

Answer 1

Answer:

acos+bsin=4

squaring both sides

a²cos² +b²sin² + 2absincos =16

Asin -bcos =3

squaring both sides

a²sin²+b²cos²-2absincos=9

adding the two equation

a²(sin²+cos²) +b²(sin²+cos²) =25

a²+b²= 25