Question

2 sin2 theta + 3 sin theta = 0
find cos theta

please answer step by step
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Answer 1

Answer:

Step-by-step explanation:

2 sin2θ + 3 cos2θ

Using the identity sin2A + cos2A = 1,

= 2(1 – cos2θ) + 3 cos2θ

= 2 – 2 cos2θ + 3 cos2θ

= 2 + cos2θ

The minimum value will be obtained when cos2θ = 0.

Therefore, the least value of 2 sin2θ + 3 cos2θ is 2.