Aspire Faculty ID #14065 · Topic: JAMIA MILLIA ISLAMIA MCA 2019 · Just now
JAMIA MILLIA ISLAMIA MCA 2019

If $|\vec{a} + \vec{b}| = |\vec{a} - \vec{b}|$, then:

Solution

Given $|\vec{a} + \vec{b}| = |\vec{a} - \vec{b}|$. Square both sides: $(\vec{a} + \vec{b})\cdot(\vec{a} + \vec{b}) = (\vec{a} - \vec{b})\cdot(\vec{a} - \vec{b})$ $\Rightarrow a^2 + b^2 + 2\vec{a}\cdot\vec{b} = a^2 + b^2 - 2\vec{a}\cdot\vec{b}$ $\Rightarrow \vec{a}\cdot\vec{b} = 0.$ Thus, $\vec{a}$ is perpendicular to $\vec{b}$.

Previous 10 Questions — JAMIA MILLIA ISLAMIA MCA 2019

Nearest first

Next 10 Questions — JAMIA MILLIA ISLAMIA MCA 2019

Ascending by ID
Ask Your Question or Put Your Review.

loading...