Question

Let$A=(1,2,3)$, $B=(3,4,5)$ then ?

• A. Direction ratios of $AB$ line are $(2,2,2)$
• B. Direction ratios of $\overline{AB}$ are $(-1,1,-1)$
• C. Direction ratios of $\overline{AB}$ are $(1,1,1)$
• D. Direction cosine od $AB$ line may be $(\frac{1}{\sqrt{3}}-\frac{1}{\sqrt{3}}-\frac{1}{\sqrt{3}})$

Answer 1

The correct option is A Direction ratios of $AB$ line are $(2,2,2)$

$\begin{array}{c}A\left(1,2,3\right)B\left(3,4,5\right)\\ direction\cos ineofABlineis\left(\frac{1}{\sqrt{3}},\frac{1}{\sqrt{3}},\frac{1}{\sqrt{3}}\right)\\ anddirectionratioofAB\left(2,2,2\right)\end{array}$