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Prove that cot2 π6+cosec 5π6+3tan2 π6=6

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प्रश्न

Prove that  `cot^2  pi/6 + cosec  (5pi)/6 + 3 tan^2  pi/6 = 6`

योग
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उत्तर

Left side = `cot^2  pi/6 + cosec (5pi)/6 + 3 tan^2  pi/6`

= `(sqrt3)^2 + cosec  (pi-pi/6)  + 3 (1/sqrt3)^2`

`(∴ cot pi/6 = sqrt3, tan  pi/6 = 1/sqrt3)`

= 3 + cosec `pi/6+ 3 xx 1/3` 

[∵cosec `(pi-θ)= cosec θ`]

= 3 + 2 + 1 = 6 = Right Side.

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अध्याय 3: Trigonometric Functions - EXERCISE 3.3 [पृष्ठ ६७]

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एनसीईआरटी Mathematics [English] Class 11
अध्याय 3 Trigonometric Functions
EXERCISE 3.3 | Q 3. | पृष्ठ ६७

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