Question

Find the missing value to the nearest hundredth. cos ? = 2/5

Answer 1

`66.42^(\circ)`

Explanation:

Let x represent the missing value for our given equation.

We have been given an equation
`\text{cos}?=(2)/(5)`. We are asked to find the missing value for our given equation.

`\text{cos}(x)=(2)/(5)`

Now, we will solve for x using arccos as:

`x=\text{cos}^(-1)((2)/(5))`

`x=66.421821521798^(\circ)`

Upon rounding our answer to nearest hundredth, we will get:

`x\approx 66.42^(\circ)`

Therefore, the missing value for our given expression would be
`66.42^(\circ)`.

Answer 2

? = arccos(2/5) ≈ 66.42° ≈ 1.16 rad