Given f(x)=sin x and g(x)=cos x, find f(g(pi/2))=0.

for this, i would just have to prove it's true or false right?

How to write 3 tenths and 5 tenths as a decimal

F(x)=x/2-2 and g(x)=2x^2+x-3 find (f+g)(x)

The diagonals of a quadrilaretral intersect at (-1,4). one of the sides of the quadrilateral is bounded by (2,7) and (-3,5) determine the coordinates of the other side in order for the quadrilaretral to be a square.