Question

cos A +sin (270+A)-sin (270-A)+cos (180+A)=n

Answer 1

CosA+sin(270+A)-sin(270-A)+cos(180+A)=n
Here n=?
As we know sin(270+A)=-cosA,sin(270-A)=-cosA,cos(180+A)=-cosA
CosA-cosA+cosA-cosA=n
n=0

Answer 2

Cos(A) is simply cos(A)

Sin(270+A)=-cos(A)

-Sin(270-A)= -[-cos(A)]=cos(A)

Cos(180+A)=cos(A)

We we add them, we get 2cos(A)

{Where I'm getting wrong??}