QS-020 · Linear Algebra · Easy

GATE DA 2025 | Question: 15

Which of the following statements is/are correct? 1. $\mathbb{R}^n$ has a unique set of orthonormal basis vectors. 2. $\mathbb{R}^n$ does not have a unique set of orthonormal basis vectors. 3. Linearly independent vectors in $\mathbb{R}^n$ are orthonormal. 4. Orthonormal vectors in $\mathbb{R}^n$ are linearly independent.

Which of the following statements is/are correct? 1. $\mathbb{R}^n$ has a unique set of orthonormal basis vectors. 2. $\mathbb{R}^n$ does not have a unique set of orthonormal basis vectors. 3. Linearly independent vectors in $\mathbb{R}^n$ are orthonormal. 4. Orthonormal vectors in $\mathbb{R}^n$ are linearly independent.
Solution Statement 1: False An orthonormal basis of $\mathbb{R}^n$ is not unique. For example, $\mathbb{R}^2$ has infinitely many orthonormal bases obtained by rotation. Statement 2: True Hence, $\mathbb{R}^n$ does not have a unique orthonormal basis. Statement 3: False Linear independence does not imply orthogonality or unit length. Statement 4: True Every set of mutually orthogonal nonzero vectors is linearly independent. Orthonormal vectors are therefore linearly independent.

Open interactive problem view

Browse more quantitative interview problems