Question

If sina+2cosa=1 then prove that 2sina-cosa=1

Answer 1

sin a+2 cos a =1 (given)

we can write this as: sin a +cos a= 1- cos a

when we square on both sides we get:

sin ^2 a +cos^a+2 sin a cos a=1+cos^2 a-2 cos a

2 cos a(sina +1)=cos^2a

2 sin a +2= cos a

2 sin a-cos a =-2

little changes yu have to do on this answer