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State whether the statement is True or False? Also give justification. If tanA = 1-cosBsinB, then tan2A = tanB

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प्रश्न

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

If tanA = `(1 - cos B)/sinB`, then tan2A = tanB

विकल्प

  • True

  • False

MCQ
सत्य या असत्य
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उत्तर

This statement is True.

Explanation:

Given that: tanA = `(1 - cosB)/sinB`

= `(2sin^2  B/2)/(2sin  B/2 cos  B/2)`

= `tan  B/2`

tan2A = `(2tanA)/(1 - tan^2 A)`

= `(2tan  B/2)/(1 - tan^2  B/2)`

∴ tan2A = tanB

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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 68 | पृष्ठ ६०

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