State the amplitude, period and phase shift of y = 3 cos(x-pi)?

Answer 1

In a sinusoidal function a*sin(bx - phi), where sin can be replaced by cos, the amplitude is a, the period is 2*pi/b, and the phase shift is phi. Inspection shows that your a is 3, b is 1, and phi is pi, so that should be enough for you to solve.

Answer 2

the amplitude of this equation is 3, period is 2pi, and phase change is pi