Express (Sin 67° + Cos 75°) in Terms of Trigonometric Ratios of the Angle Between 0° and 45°. - Mathematics

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Sum

Express (sin 67° + cos 75°) in terms of trigonometric ratios of the angle between 0° and 45°.

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Solution

(sin 67° + cos 75°)
= (sin (90°23°) + cos (90°15°))      .....( sin(90°θ) = cosθ and cos(90°θ) = sinθ)
= (cos 23°+ sin 15°)

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2018-2019 (March) 30/4/3

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