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2 sin^2 + sin x - 3 = 0

User Woblob
by
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1 Answer

5 votes

Answer:

x = 2 π n_1 + π/2 for n_1 element Z

or x = π + sin^(-1)(3/2) + 2 π n_2 for n_2 element Z or x = 2 π n_3 - sin^(-1)(3/2) for n_3 element Z

Explanation:

Solve for x:

-3 + sin(x) + 2 sin^2(x) = 0

The left hand side factors into a product with two terms:

(sin(x) - 1) (2 sin(x) + 3) = 0

Split into two equations:

sin(x) - 1 = 0 or 2 sin(x) + 3 = 0

Add 1 to both sides:

sin(x) = 1 or 2 sin(x) + 3 = 0

Take the inverse sine of both sides:

x = 2 π n_1 + π/2 for n_1 element Z

or 2 sin(x) + 3 = 0

Subtract 3 from both sides:

x = 2 π n_1 + π/2 for n_1 element Z

or 2 sin(x) = -3

Divide both sides by 2:

x = 2 π n_1 + π/2 for n_1 element Z

or sin(x) = -3/2

Take the inverse sine of both sides:

Answer: x = 2 π n_1 + π/2 for n_1 element Z

or x = π + sin^(-1)(3/2) + 2 π n_2 for n_2 element Z or x = 2 π n_3 - sin^(-1)(3/2) for n_3 element Z

User Deepak Agarwal
by
3.0k points