Thread: y = sine x = cos x

If y = A*sin(Bx + C) + D is substituted as y = -1.5 sin(x + π/4) + 4, what

would the cosine function be in order to match the graph of said sine

function?

Originally Posted by zacharyrod

If y = A*sin(Bx + C) + D is substituted as y = -1.5 sin(x + π/4) + 4, what

would the cosine function be in order to match the graph of said sine

function?

Note that . You can show this using the subtraction formula for sin. In terms of the graphs it means the graph of cos(x) is shifted by pi/2 to the right on the x axis

Only C would change as it's a phase difference

-1.5cos(x-π/4)+4