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Solve for x in 4 sinx – 4 cos² x = -1 for 0 = x = 360⁰.

Solve for x in 4 sinx – 4 cos² x = -1 for 0 ≤ x ≤ 360⁰.

Answers

4Sin x – 4 (1 – sin²x ) = -1
4 sin x – 4sin² x + 1 = 0
let sin x be K
4k² + 4k – 3 = 0
(2k-1)(2k+3) = 0
2k = 1 or 2k = -3
k = ½
sin x = ½
x = 30, 15.0

Kavungya answered the question on November 15, 2019 at 05:27

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