Question

Simplify 1+cos(x+pi/2)+cos(x-pi/2) , steps .

Answer 1

1+cos(x+pi/2)+cos(x-pi/2)
we know cos (-x)=cos (x)
using this for the last term
1+cos(pi/2+x)+cos(pi/2-x)
now cos(pi/2+x)=-sin x
and cos (pi/2-x)=sin x
using these in the equation
1-sin x+sin x
1

Answer 2

simplified form =1

Answer 3

Thanks!