Let $\vec{a}=5 \hat{i}-\hat{j}-3 \hat{k}$ and $\vec{b}=\hat{i}+3 \hat{j}+5 \hat{k}$ be two vectors.

Question

Let $\vec{a}=5 \hat{i}-\hat{j}-3 \hat{k}$ and $\vec{b}=\hat{i}+3 \hat{j}+5 \hat{k}$ be two vectors. Then which one of the following statements is TRUE?\

Professor PC Thomas Classes · Answer

$\vec{a}=5 \hat{i}-\hat{j}-3 \hat{k} \quad \vec{b}=\hat{i}+3 \hat{j}+5 \hat{k}$ Projection of $\vec{a}$ and $\vec{b}$ is\ $\vec{a} \cdot \hat{b}=\frac{\vec{a} \cdot \vec{b}}{|\vec{b}|}=\frac{5-3-15}{\sqrt{35}}=\frac{-13}{\sqrt{35}}$\