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If \( \Large \triangle ABC \) is right angled at C, then what is cos (A + B) + Sin (A + B) equal to?

A) 0
B) \( \Large \frac{1}{2} \)
C) 1
D) 2

Correct Answer:



C) 1

Description for Correct answer:

In \( \Large \triangle ABC \), if \( \Large \angle C \) is 90 \(^{\circ} \), then

\( \Large \angle A+ \angle B \) = 180 \(^{\circ} \) - 90 \(^{\circ} \) = 90 \(^{\circ} \)

Now, cos (A + B) + sin(A + B)

=cos 90 \(^{\circ} \)+ sin 90 \(^{\circ} \) = 0+1=1

Part of solved Trigonometry questions and answers : >> Elementary Mathematics >> Trigonometry

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Similar Questions

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