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Prove that: sin2 π6+cos2 π3-tan2 π4=-12

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प्रश्न

Prove that: `sin^2  pi/6 + cos^2  pi/3 - tan^2  pi/4 = -1/2`

योग
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उत्तर

Left side = `sin^2 pi/6 + cos^2 pi/3 - tan^2 π/4`

= `(1/2)^2 + (1/2)^2` - 12

(∵ sin `π/6 = 1/2 , cos π/3 = 1/2 , tan pi/4` = 1)

= `1/4+1/4-1=1/2` 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 1. | पृष्ठ ६७

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