find a solution with 0<x<pi in radians

Question

3 cos x = 0.654 and round the answer to three decimal places

Answer 1

3cos(x) = 0.654 [divide both sides by 3 to get:

cos(x) = 0.654/3

cos(x) = 0.218 [now, take the inverse cosine of both sides to get:

cos^-1(cos(x)) = cos^-1(0.218)

x = cos^-1(0.218) [now, plug this into a calculator

x = 1.351 radians