question_answer

If the projections of a line segment on the \[x,y\] and \[z\] axes in 3-dimensional space are 2, 3 anA5 respectively, then the length of line segment is

A) 6                                             

B) 7

C) 9                                             

D) 12

Correct Answer: B

Solution :

\[\therefore \]\[AB=\sqrt{{{({{x}_{1}}-{{x}_{2}})}^{2}}+{{({{y}_{1}}+{{y}_{2}})}^{2}}+{{({{z}_{1}}-{{z}_{2}})}^{2}}}\] \[=\sqrt{4+9+36}=\sqrt{49}=7\]