Question

3. Find magnitude of 3i + 4j + 5k (A) 2sqrt(5) (B) 4sqrt(5) (C) 5sqrt(2) (D) 5sqrt(5) N​

Answer 1

   Answer:

   $5\sqrt{2}$

   Step-by-step explanation:

   The given vector is $3{i} + 4j + 5k$

   We know that the magnitude of any vector $a = xi + yj + zk$ is

   $|a| = \sqrt{x^{2} + y^{2} + z^{2} }$

⇒ In our case, the magnitude of $3{i} + 4j + 5k$ = $\sqrt{3^{2} + 4^{2} + 5^{2} }$

⇒ $\sqrt{9+16+25}$

⇒ $\sqrt{25+25}$

∴ $5\sqrt{2}$ is the magnitude of $3{i} + 4j + 5k$