If $|\vec{a}|=10,|\vec{b}|=2$ and $\vec{a} \cdot \vec{b}=12$, then the value of $|\vec{a} imes \ve

Question

If $|\vec{a}|=10,|\vec{b}|=2$ and $\vec{a} \cdot \vec{b}=12$, then the value of $|\vec{a} 	imes \vec{b}|$ is

Professor PC Thomas Classes · Answer

$|\vec{a}	imes\vec{b}|^2 + (\vec{a}\cdot\vec{b})^2 = |\vec{a}|^2 |\vec{b}|^2 \implies |\vec{a}	imes\vec{b}|^2 + 144 = 400 \implies |\vec{a}	imes\vec{b}| = 16$.