SOLUTION: Find all degree solutions. (Enter your answers as a comma-separated list. Let k be any integer.)
2 cos^2 5θ + 3 cos 5θ + 1 = 0
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-> SOLUTION: Find all degree solutions. (Enter your answers as a comma-separated list. Let k be any integer.)
2 cos^2 5θ + 3 cos 5θ + 1 = 0
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Question 1098977: Find all degree solutions. (Enter your answers as a comma-separated list. Let k be any integer.)
2 cos^2 5θ + 3 cos 5θ + 1 = 0 Answer by ikleyn(52817) (Show Source):
Introduce new variable x = .
Then your equation will take the form
= 0.
It is a quadratic equation. Apply the quadratic formula to solve it:
= = .
1) Case 1: = = ====> = ====> = = .
2) Case 2: = = -1 ====> = + .
Answer. The solutions are , and .
