Question

How do you graph `y=3 cos (x/5)`?

Answer 1

See explanation

Explanation:

The standardised `cos(theta)` has a max of +1 and a min of -1.

Thus `3xxcos(theta)` changes this to a max of 3 and a min of -3.
Su the up and down is increased by a factor of 3.

The `x/5` reads a point on graph of `cos(x/5)` and plots it at `x`

Consequently `x/5` opens up the plot of `cos(x)` like stretching a spring and in doing so expanding it horizontally by a factor of 5.

`color(purple)("The graph below uses radian measure for the x-axis")`