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Quadratics in trigonometry. Please help?

Quadratics in trigonometry. Please help?-example-1
User Amcelwee
by
6.6k points

1 Answer

3 votes

Answer:

x = 5π/6, 3π/2.

Explanation:

cot^2 x- csc x - 1 = 0

cos^2 x / sin^2x - 1/ sin x - 1 = 0

(1 - sin^2x) / sin^2 x - 1 / sin x - 1 = 0

Multiply though by sin^2 x:

1 - sin^2x - sin x - sin^2 x = 0

2 sin^2 x + sin x - 1 = 0

(2 sinx - 1)( sin x + 1)

sin x = 1/2, -1.

when sin x = 1/2, x = π/6, 5π/6

when sin x = -1 , x = 3π/2.


User Simon Steele
by
7.4k points
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