Question

Y=-2sin(x-3.14/2) the equation is mult. (Y) by (-2) && down 3.14/2 or right 3.14/2 ? Help plz

Answer 1

yes, the -2 is the amplitude. The sine function range is -1 to 1, so the number in front increases amplitude.

The adding or taking off things to the inner part on the angle will change the phase, shift the graph left or dight. It is opposite, if it is x - B, shift Right, if x + b, same as x - (-b), shifts left,

Graph
y = A*sin(x-B)
hit add sliders, and you can change A and B and watch what happens to the graph...
https://www.desmos.com/calculator