Function Sketching

Question

Sketch one period of the function given, State what the amplitude, phase, shift, period, and vertical translation are. Plot the five points. 

y= -cos(2x-pi).

 

Please tell me step by step and tell me each point and not sketch it, and as well tell me how I should know how to put each point.

Answer 1

y=-cos[2(x-pi/2)]

vertical shift=0= D

period =pi = 2pi/B

phase shift =pi/2=C

amplitude =1 =|A-D|

y=AcosB(x-C) +D