### Question Asked by a Student from EXXAMM.com Team

Q 2470601516.
NDA 2007 Paper 1

Assertion : If (: l, m, n :) are directiod cosines of a line, there can be a line whose direction cosines are (: sqrt ((l^2+m^2)/2) , sqrt((m^2+n^2)/2) , sqrt((n^2 +l^2)/2) :)

Reason : The sum of direction cosines of a line is unity.

A Both A and R individually true and R is the correct explanation of A
B Both A and R are individually true but R is not the correct explanation of A
C A is true but R is false
D A is false but R is true

#### HINT

(Provided By a Student and Checked/Corrected by EXXAMM.com Team)

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