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If sin θ + cosθ = 3 then the value of sin4 q is : sin θ - cosθ
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2 5 -
1 5 -
4 5 -
3 5 - None of these
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Correct Option: E
| = | sinθ - cosθ | 1 |
By componendo and dividendo
| = | sin θ + cos θ - sin θ + cosθ | 3 - 1 |
| ⇒ | = | 2 cosθ | 2 |
⇒ tanθ = 2
| ∴ cotθ = | 2 |
∴ cosecθ = √1 + cot² θ
| ∴ sin θ = | √5 |
| sin4θ = | 25 |
