Problem

Find all solutions to the equation $10 \cos (x+2)=2$ for $0 \leq x \leq 2 \pi$.
Enter your answers in increasing order rounded to three decimal places.

Answer

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Answer

The final solution is \(\boxed{3.014}\).

Steps

Step 1 :We have that \(10 \cos (x+2)=2\).

Step 2 :Divide both sides by 10, we get \(\cos (x+2)=0.2\).

Step 3 :Take the inverse cosine of both sides, we get \(x+2=\cos^{-1}(0.2)\).

Step 4 :Since \(0 \leq x \leq 2 \pi\), we know that \(0 \leq x+2 \leq 2 \pi + 2\), which means \(-2 \leq x \leq 2 \pi\).

Step 5 :\(\cos^{-1}(0.2)\) has two solutions in the range \(-2 \leq x \leq 2 \pi\), which are approximately 1.369 and 5.014.

Step 6 :Subtract 2 from both solutions, we get \(x \approx -0.631\) and \(x \approx 3.014\).

Step 7 :But \(-0.631\) is not in the range \(0 \leq x \leq 2 \pi\), so we discard it.

Step 8 :The final solution is \(\boxed{3.014}\).

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