In ∆ ABC, AB = a – b, AC = √a² + b²

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In ∆ ABC, AB = a – b, AC = √a² + b² and BC = √2ab, then find angle B.

1. 60°
2. 30°
3. 90°
4. 45°

Correct Option: C

According to question , we draw a figure

Given , AB = a – b; BC = √2ab ;
AC = √a² + b²
∴ AB² + BC² = (a – b)² + (√2ab)²
AB² + BC² = a² + b² – 2ab + 2ab = a² + b² = AC²
∴ ∠ABC = 90°