Question

Compare the three functions below. Which has a greater period? A) y = 3cos(2x+1), B) y=5cos(4x +8), and C) y=cos(2x+4) (4.3)

Answer 1

Explanation:

Given functions are

A) y = 3cos(2x+1), B) y=5cos(4x +8), and C) y=cos(2x+4) (4.3)

or we can rewrite :

A) y = 3cos(2x+1), B) y=5cos(4x +8), and C) y=(4.3)cos(2x+4)

We need to find their periods which is basically (2pi/coefficient of x) of the given cosine function.

So the period of given choices are:

A)
`(2\pi)/(2)`, B)
`(2\pi)/(4)`, and C)
`(2\pi)/(2)`

or

A)
`\pi`, B)
`(\pi)/(2)`, and C)
`\pi`

Greatest of them is
`\pi`

So the correct choice is A) y = 3cos(2x+1) and C) y=cos(2x+4) (4.3)