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Mathematics

1 answer:

Marina86 [1]3 years ago

6 0

$\large\color{lime}\boxed{\colorbox{black}{Answer : - }}$

We know that, in ∆ABC,

∠A+∠B+∠C = 180°

But the triangle is right angled at C

ie., ∠C = 90°

Therefore, ∠A+∠B+ 90° = 180°

⇒ ∠A + ∠B = 90°

Therefore, <u>cos(A + B) = cos 90º = 0</u>

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aleksandrvk [35]

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