What is the general solution of the trigonometric equation cos(x) = 1/2?
Answer and explanation
Correct answer: A. x = 2npi +/- pi/3
- Step 1: Principal value: cos(pi/3) = 1/2. Step 2. General solution for cos(x) = cos(alpha) is x = 2npi +/- alpha. Step 3. Therefore, x = 2npi +/- pi/3 where n is any integer. *Answer: x = 2npi +/- pi/3. Why not the others: 2n*pi +/- pi/6 is for cos(x) = sqrt(3)/2.
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