Express cot 85^{circ}+cos 75^{circ} in terms of trigonometric ratios of angles between 0^{circ} and

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8. Introduction to Trigonometry

easy

Express $\cot 85^{\circ}+\cos 75^{\circ}$ in terms of trigonometric ratios of angles between $0^{\circ}$ and $45^{\circ}$

Option A

Option B

Option C

Option D

Solution

$\cot 85^{\circ}+\cos 75^{\circ}$ $=\cot \left(90^{\circ}-5^{\circ}\right)+\cos \left(90^{\circ}-15^{\circ}\right)$

$=\tan 5^{\circ}+\sin 15^{\circ}$

Standard 10

Mathematics

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