What is the angle between the lines whose direction cosines are proportional to (2, 3, 4) and (1, -2, 1), respecti

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

Q 2319156919.     What is the angle between the lines whose
direction cosines are proportional to (2, 3, 4) and
(1, -2, 1), respectively?
NDA 2011 Paper 1
A

90^(circ)

B

60^(circ)

C

45^(circ)

D

30^(circ)

#### HINT

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

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