Question

${sin}^{2} \alpha + sin \alpha \: - 1 = 0$
Then value of
$\alpha$

Answer 1

${sin}^{2} \alpha + sin \alpha - 1 = 0 \\ sin(sin + \alpha ) - 1 = 0 \\ sin \alpha + \alpha - 1 = 0 \\ \alpha (sin + 1) = 1 \\ \alpha = \frac{1}{(sin + 1)}$

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