Question

The vectors $5i + 8j$and$2i + 7j$are added. The magnitude of the sum of these vector is

• A. $\sqrt{274}$
• B. 38
• C. 238
• D. 560

Answer 1

Answer: (A)

$\sqrt{274}$

Answer 2

Sum of the vectors

$\overset{\rightarrow}{R} = 5\widehat{i} + 8\widehat{j} + 2\widehat{i} + 7\widehat{j} = 7\widehat{i} + 15\widehat{j}$

Magnitude of $\overset{\rightarrow}{R} = |\overset{\rightarrow}{R}| = \sqrt{49 + 225} = \sqrt{274}$