The sides of a $ riangle A B C$ are given by $a=3, b=5$ and $c=3$. Then, $\cos A=$

Question

The sides of a $	riangle A B C$ are given by $a=3, b=5$ and $c=3$. Then, $\cos A=$

Aicharya · Accepted Answer

$\begin{aligned} & a=3, b=5, c=3 \ & \cos A=\frac{b^2+c^2-a^2}{2 b c}\end{aligned}$ $\begin{aligned} & =\frac{25+9-9}{2 	imes 5 	imes 3} \ & =\frac{25}{30}=\frac{5}{6}\end{aligned}$

The sides of a $\triangle A B C$ are given by $a=3, b=5$ and $c=3$. Then, $\cos A=$

Solution