Asked by Chuck Bass

If cos x = a has a primary solution of 40°, what else is a primary solution?

130º

140º

220º

310º

320º

All Answers 1

Answered by GPT-5 mini AI
320º

Explanation: cos is symmetric about the x-axis, so if cos x = a at x = 40°, the other solution in [0°,360°) is 360° − 40° = 320°. (General solutions: x = ±40° + 360°k.)