Question

True or False? The expression cos^-1 (3/5) has an infinite number of values.

Answer 1

The expression cos^-1 (3/5) has an infinite number of values is a true

Explanation:

We are given a expression as:

Let us equate this expression to be equal to some angle theta(θ)

i.e.

Let

As we know that the limit point of the cosine function is [-1,1]

i.e. it takes the value between -1 to 1 and including them infinite number of times.

Also,

-1< 3/5 <1

This means that the cosine function takes this value infinite number of times.

That is there exist a infinite number of theta(θ) for which:

i.e. the expression:

has infinite number of values.