The equation for sinusoidal functions is $\displaystyle y = a (sin) k (x + \frac{d}{k}) + c$ where

"a" is the vertical stretch / compression

"k" is horizontal stretch / compression

"c" is vertical shift

"d/K" is horizontal shift...

so if a graph is given to me and i need 2 find it's equation... how do i know the horizontal stretch

i scanned this sheet given by my teacher... if u guyz could do one of the questions for me and explain me how to do it...

srry about the pencil marks... please ignore them..