Question

Given cos A = .29 find the angle A in radians. Round your answer to the nearest hundredth.Answer 1.19 radians 1.28 radians 1.34 radians 1.46 radians

Answer 1

Use the inverse cosine button on your calculator. Make sure it's in radians. The answer is 1.28

Answer 2

Answer: The correct option is (B) 1.28 radians.

Step-by-step explanation: We are given that for an angle A :

`\cos A=0.29.`

We are to find the measure of angle A in radians.

We know that the relation between degree and radians is given by

`80^\circ=\pi~\textup{radians}\\\\\\\Rightarrow 180^\circ=(22)/(7)~\textup{radians}.`

Now, we have

`\cos A=0.29\\\\\Rightarrow A=\cos^(-1)(0.29)\\\\\\\Rightarrow A=73.14^\circ.`

Again,

`180^\circ=(22)/(7)\\\\\Rightarrow 1^\circ=(22)/(7*180)\\\\\Rightarrow 73.14^\circ=(22)/(1260)*73.14=1.277=1.28~\textup{radians}.`

Thus, the measure of angle A in radians is 1.28 radians.

Option (B) is CORRECT.