With usual notations in $ riangle A B C$ if $a^2+b^2-c^2=a b$, then measure of angle $C$ is

Question

With usual notations in $	riangle A B C$ if $a^2+b^2-c^2=a b$, then measure of angle $C$ is

Aicharya · Accepted Answer

$\begin{aligned} & a^2+b^2-c^2=a b \ & \Rightarrow \frac{a^2+b^2-c^2}{2 a b}=\frac{1}{2} \ & \Rightarrow \cos c=\frac{1}{2} \ & \Rightarrow c=\frac{\pi}{3}\end{aligned}$

With usual notations in $\triangle A B C$ if $a^2+b^2-c^2=a b$, then measure of angle $C$ is

Solution