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State whether the statement is True or False? Also give justification. If tanθ + tan2θ + 3 tanθ tan2θ = 3, then θ = nnπ3+π9

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प्रश्न

State whether the statement is True or False? Also give justification.

If tanθ + tan2θ + `sqrt(3)` tanθ tan2θ = `sqrt(3)`, then θ = `("n"pi)/3 + pi/9`

विकल्प

  • True

  • False

MCQ
सत्य या असत्य
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उत्तर

This statement is True.

Explanation:

Given that: tanθ + tan2θ + `sqrt(3)` tanθ tan2θ = `sqrt(3)`

⇒ tanθ + tan2θ = `sqrt(3) - sqrt(3) tan theta tan 2theta`

⇒ tanθ + tan2θ = `sqrt(3)  (1 - tan theta tan 2theta)`

⇒ `(tan theta + tan 2theta)/(1 - tan theta tan 2theta) = sqrt(3)`

⇒ tan(θ + 2θ) = `sqrt(3)`

⇒ tan3θ = `tan  pi/3`

∴ 3θ = `"n"pi + pi/3`

So θ = `("n"pi)/3 + pi/9`

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अध्याय 3: Trigonometric Functions - Exercise [पृष्ठ ६०]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 3 Trigonometric Functions
Exercise | Q 74 | पृष्ठ ६०

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