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The angle between the lines whose direct...

The angle between the lines whose direction cosines are l, m, n and m-n, n-l, l-m is......

A

`pi/6`

B

`pi/2`

C

`pi/3`

D

`pi/4`

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The correct Answer is:
B
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KUMAR PRAKASHAN-THREE DIMENSIONAL GEOMETRY-MULTIPLE CHOICE QUESTIONS (MCQs)
  1. The cartesian equation of the line passing through (2,2,-3) and (1,3,5...

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  2. The equation of the line passes through (2,-3,5) and makes equal with ...

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  3. The angle between the lines whose direction cosines are l, m, n and m-...

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  4. The vector equation of the line (3-x)/(3) = (2y - 3)/(5) = z/2 is .......

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  5. The lines bar r = (-1,2,5) + k (-1,2,5), k in R and bar r = (-3,1,5) ...

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  6. The vector equation of the line joining the pionts hat(i) - 2hat (j)+ ...

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  7. If bar = hat i + hat j and bar b = 2 hat i - hat k then the intersect...

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  8. The co-ordinats of a point on the line passing through the pionts (1,-...

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  9. The equation of the line passing through hat i + 3 hat j + 2 hat k a...

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  10. The shortest distance of the lines bar r1 = 4 hat i -3 hat j - hat k +...

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  11. The direction cosines of the line drawn from P(-5,3,1) and Q(1,5,-2) i...

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  12. The angle between the two diagonals of a cube is .....

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  13. The angle between the two diagonals of a cube is .....

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  14. A line makes the angle alpha, beta , gamma and delta with the diagonal...

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  15. The edge of a cube is of length of a. The shortest distance between th...

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  16. The projection of a line on the axes are 9,12, and 8. The length of th...

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  17. The straight lines whose direciton cosines are given by al + bm + cn =...

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  18. The foot of perpendicular drawn from the point P(1,0,2) on the line (x...

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  19. The foot of perpendicular drawn from the point P(1,0,2) on the line (x...

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  20. Prove that if the lines x = ay + b, z = cy + d and x = a'y + b', z = c...

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