Correct option is C

Given:

a cot = b

Theorem Used: Pythagoras theorem

If ABC is a triangle∠B= 90⁰

​$$AB^2 + BC^2 = AC^2$$

Solution:

​$$AB^2 + BC^2 = AC^2 \\\text{Then, } a^2 + b^2 = AC^2 \\AC = \sqrt{a^2 + b^2} \\\cos \theta = \frac{b}{\sqrt{a^2 + b^2}} \\\sin \theta = \frac{a}{\sqrt{a^2 + b^2}}$$

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