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Question
If Sin (A + B) = 1 and cos (A – B) = 1, 0° < A + B ≤ 90° A ≥ B. Find A & B
Solution
Sin(A + B) = 1
∴ Sin (A + B) = Sin 90°
A + B = 90° …(i)
Cos (A – B) = 1
Cos (A – B) = cos 0°
A – B = 0° …(ii)
Adding (i) and (ii) we get
A + B = 90°
`(A - B = 0^@)/(A = 90^@)` `A = 45^@`
A – B = 0
A = B => B = 45°
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