Could someone explain how the graph of y=cos x can be obtained by translating the graph of y=sinx? Thank you!
2 answers
horizontally phase shift the graph of y=sin(x) by pi/4 units to the left and reflect the graph over the x axis to acquire the graph y=cos(x)
sorry - no reflection was indicated. just translation.
sinx = sin(180-x)
cosx = sin(90-x) = sin(180-(90-x)) = sin(90+x)
check:
sin(90+x) = sin90 cosx + cos90 sinx = cosx
sinx = sin(180-x)
cosx = sin(90-x) = sin(180-(90-x)) = sin(90+x)
check:
sin(90+x) = sin90 cosx + cos90 sinx = cosx