The number of values of \( \alpha \) in \( [0,2 \pi] \) for which \( 2 \sin ^{3} \alpha-7 \sin ^{2} \alpha+7 \sin \alpha=2 \), is:

JEE MATHEMATICS MCQ: TRIGONOMETRIC EQUATIONS

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Analyzing +4 | -1

The number of values of

\alpha

[0,2 \pi]

for which

2 \sin ^{3} \alpha-7 \sin ^{2} \alpha+7 \sin \alpha=2

, is:

View answer and explanation

Correct option: C

Option C (3) is correct because solving the equation

2 \sin ^{3} \alpha-7 \sin ^{2} \alpha+7 \sin \alpha=2

gives three solutions in the interval [0, 2

\pi

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