Question

What is the numerical value of the vector $3\hat{i}+4\hat{j}+4\hat{k}$

• A. $\sqrt{31}$
• B. $\sqrt{41}$
• C. $\sqrt{51}$
• D. $9\sqrt{2}$

Answer 1

The correct option is B $\sqrt{41}$

$\overline{A}=a\hat{i}+b\hat{j}+c\hat{k}$ , $|\overline{A}|$=$\sqrt{a^2+b^2+c^2}$,

$|\overline{A}|$=$\sqrt{3^2+4^2+4^2}$=$\sqrt{41}$