How do you graph y = 2 cos 3 (x - (pi/4))y=2cos3(x(π4))?

1 Answer
Jul 4, 2018

As below.

Explanation:

Standard cosine function is y = A cos (Bx - C) + Dy=Acos(BxC)+D

"Given : " y = 2 cos(3x - (3pi)/4) Given : y=2cos(3x3π4)

A = 2, B = 3, C = (3pi)/4, D = 0A=2,B=3,C=3π4,D=0

Amplitude = |A| = 2Amplitude=|A|=2

"Period " = (2pi) / |B| = (2pi) / 3Period =2π|B|=2π3

"Phase Shift " = -C / B = -((3pi)/4) / 3 = -(pi/4),color(crimson)( pi/4 " to the LEFT"Phase Shift =CB=3π43=(π4),π4 to the LEFT

"Vertical Shift " = D = 0Vertical Shift =D=0

graph{2 cos (3x - (3pi)/4) [-10, 10, -5, 5]}