1.

If the value of tanθ + cotθ = √3, then find the value of tan6θ + cot6θ.1. -22. -13. -34. -4

Answer» Correct Answer - Option 1 : -2

Given:

tanθ + cotθ = √3

Formula used:

a3 + b3 = (a + b)3 - 3ab(a + b)

a2 + b2 = (a + b)2 - 2(a × b)

tanθ × cotθ = 1

Calculation:

tanθ + cotθ = √3

Taking cube on both sides, we get

(tanθ + cotθ)3 = (√3)3

⇒ tan3θ + cot3θ + 3 × tanθ × cotθ × (tanθ + cotθ) = 3√3

⇒ tan3θ + cot3θ + 3√3  = 3√3

⇒ tan3θ + cot3θ = 0  

Taking square on the both sides

(tan3θ + cot3θ)2 = 0

⇒ tan6θ + cot6θ + 2 × tan3θ × cot3θ = 0

⇒ tan6θ + cot6θ + 2 = 0    

⇒ tan6θ + cot6θ = - 2

∴ The value of tan6θ + cot6θ is - 2.



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