Mathematics

If △ABC is right angled at C, then the value of cos (A + B) is
0
1
$\dfrac{1}{2}$
$\dfrac{\sqrt{3}}{2}$

Trigonometrical Ratios

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Answer

In △ABC,

⇒ ∠A + ∠B + ∠C = 180°

⇒ ∠A + ∠B + 90° = 180°

⇒ ∠A + ∠B = 90°.

⇒ cos (A + B) = cos 90° = 0.

Hence, Option 1 is the correct option.

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