If this question is asking for `cos (cos^-1(2/5))` then the answer is a matter of understanding the difference between cosine and inverse cosine.

Cosine represents a ratio between two lengths. This ratio will always be the same for a given angle in a right triangle. Thus, the consine of an * ...*

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If this question is asking for `cos (cos^-1(2/5))` then the answer is a matter of understanding the difference between cosine and inverse cosine.

Cosine represents a ratio between two lengths. This ratio will always be the same for a given angle in a right triangle. Thus, the consine of an *angle*, θ, will give us a *ratio*.

The inverse cosine works in the opposite direction: it takes a *ratio*, and tells us what *angle* provides that ratio in a right triangle.

Therefore, `cos^-1(2/5)` will tell us the angle. However, the question is asking for the cosine of this angle.

**The cosine of this angle is 2/5.**

Each counterclockwise rotation is `(+360˚)`

`6.8*360 = 2448`

**6.8 counterclockwise rotations equals 2448˚.**

Find `cos^(-1) (2/5).`

`cos^-1 = 66.422` ˚