Q30 of 35 Page 288

If ∠ A and ∠ B are acute angles such that sinA = sinB then prove that ∠ A = ∠ B.

Consider ΔABC to be a right - angled triangle.



∴ sinA = BC/AB


sinB = AC/AB


Given that sinA = sinB


BC/AB = AC/AB


→ BC = AC


→ ∠ A = ∠ B (In a triangle, angles opposite to equal angles are equal)


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