A) 30°
B) 40°
C) 50°
D) 60°
Correct Answer: D
Solution :
\[\frac{\sin \frac{A+\delta \,m}{2}}{\sin \frac{A}{2}}=\mu ,\] But \[\frac{A+{{\delta }_{m}}}{2}=i={{45}^{o}}\] So \[\frac{\sin {{45}^{o}}}{\sin (A/2)}=\sqrt{2}\Rightarrow \frac{1}{2}=\sin \frac{A}{2}\Rightarrow A={{60}^{o}}\]You need to login to perform this action.
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