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Evaluate the Following Sin2 30° + Sin2 45° + Sin2 60° + Sin2 90° - Mathematics

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प्रश्न

Evaluate the following

sin2 30° + sin2 45° + sin2 60° + sin2 90°

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उत्तर

sin2 30° + sin2 45° + sin2 60° + sin2 90°  .....(1)

`sin 30^@ = 1/2     sin 45^@ = 1/sqrt2`

`sin 60^@ = sqrt3/2   sin 90^@ = 1`

By substituting above values in (i), we get

`= [1/2]^2 + [1/sqrt2]^2 + [sqrt3/2]^2 + [1]^2`

`= 1/4 + 1/2 + 3/4 + 1 => (1 + 3)/4 + (1 + 2)/2`

`=> 1 + 3/2 = (2 + 3)/2 = 5/2`

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अध्याय 10: Trigonometric Ratios - Exercise 10.2 [पृष्ठ ४१]

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आरडी शर्मा Mathematics [English] Class 10
अध्याय 10 Trigonometric Ratios
Exercise 10.2 | Q 4 | पृष्ठ ४१

वीडियो ट्यूटोरियलVIEW ALL [2]

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