Question

What is the amplitude and period of f(t)= -cos 3t?

Answer 1

option c

amplitude 1 ; period 2π/3

Explanation:

Given in the question a function,

f(t)=-cos3t

Standard form of cosine function is

f(t)=acos(bt)

Amplitude is given by = |a|

Period of function is given by = 2π/b

So the amplitude is |-1| = 1

the period is 2π/3 = 2π/3

Answer 2

c. The amplitude is 1.

The period is
`(2\pi)/(3)`

Explanation:

The given cosine function is ;

`f(t)=-\cos 3t`

This function is of the form;

`f(t)=a\cos bt`

The amplitude is given by |a|

|-1|=1

The period of this function is given by;

`T=(2\pi)/(|b|)`

`T=(2\pi)/(|3|)=(2\pi)/(3)`

The amplitude is 1.

The period is
`(2\pi)/(3)`