Question

The projection of the line segment joining the points (–1, 0, 3) and (2, 5, 1) on the line whose direction ratios are 6, 2, 3 is

• A. $\frac { 10 } { 7 }$
• B. $\frac { 22 } { 7 }$
• C. $\frac { 18 } { 7 }$
• D. None of these

Answer 1

Answer: (B)

$\frac { 22 } { 7 }$

Answer 2

Obviously, the projection

= $[ 2 - ( - 1 ) ] \frac { 6 } { 7 } + [ 5 - 0 ] \frac { 2 } { 7 } + [ 1 - 3 ] \frac { 6 } { 7 }$ = $\frac { 18 + 10 - 6 } { 7 }$= $\frac { 22 } { 7 }$ .