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Prove that sin 4α = 4tanα1-tan2α(1+tan2α)2

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प्रश्न

Prove that sin 4α = `4 tan alpha (1 - tan^2alpha)/(1 + tan^2 alpha)^2`

योग
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उत्तर

sin 4α = sin 2(2α)

= `(2tan(2alpha))/(1 + tan^2 (2alpha))`

= `(2((2tan alpha)/(1 -  tan^2 alpha)))/(1 + ((2 tan alpha)/(1 -  tan^2 alpha))^2`

= `((4 tan alpha)/(1 -  tan^2 alpha))/(((1 - tan^2 alpha)^2 +  4 tan^2 alpha)/(1 -  tan^2 alpha)^2)`

= `(4 tan alpha (1 - tan^2 alpha))/(1 + tan^2 alpha - 2 tan^2 alpha + 4 tan^2 alpha)`

= `(4 tan alpha (1 - tan^2 alpha))/(1 + 2 tan^2 alpha + tan^4 alpha)`

sin 4α = `(4 tan alpha (1 - tan^2 alpha))/(1 + tan^2 alpha)^2`

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Trigonometric Functions and Their Properties
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Trigonometry - Exercise 3.5 [पृष्ठ ११८]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 3 Trigonometry
Exercise 3.5 | Q 5 | पृष्ठ ११८

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