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If alpha,beta,gamma are the direction an...

If `alpha,beta,gamma` are the direction angles of a line
(i)Show that `sin^2 alpha + sin^2 beta +sin^2 gamma=2`.
(ii)Find the value of `cos2alpha +cos2beta+cos2gamma`.

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NEW JOYTHI PUBLICATION-THREE DIMENSIONAL GEOMETRY-Objective
  1. If alpha,beta,gamma are the direction angles of a line (i)Show that ...

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  2. The distance between x axis and the point (3,12,5) is

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  3. The perpendicular distance of the point (6,5,8) from y-axis

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  4. If 1/2,1/3,n are the direction cosines of a line , then the value of ...

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  5. A line makes angles of 45^@ and 60^@ with the z-axis and the x-axis re...

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  6. If direction cosines of a line are (1)/(c),(1)/(c),(1)/(c)," then. "

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  7. The coordinates of a point P are (3,12,4) w.r.t. the origin O. Then th...

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  8. The direction cosines of a line that makes equal angles with the three...

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  9. If the direction cosines of a line are k,k,k , then

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  10. The direction cosines of a straight line, whose projections on the coo...

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  11. The vector equation of the straight line (1-x)/3 =(y+1)/(-2) =(3-z)/(-...

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  12. The line (x-x1)/0=(y-y1)/1=(z-z1)/2 is

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  13. A unit vector parallel to the straight line (x-2)/3=(3+y)/(-1) = (z-2)...

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  14. The two lines x=ay+b, z=cy+d and x=a'y+b', z=c'y+d will be perpendicul...

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  15. If the vector equation of a line (x-2)/2=(2y-5)/(-3) =z+1 is vecr=2hat...

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  16. If the staight line (x-1)/k=(y-2)/2=(z-3)/3 and (x-2)/3=(y-3)/k =(z-1)...

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  17. The equation of the line joining the points (-3,4,11) and (1,-2,7) is

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  18. The vector equation of the line 6x-3=3y+4=2z-2 is

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  19. The angle between the staight lines (x+1)/2=(y-2)/5=(z+3)/4 and (x-1)/...

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  20. If the lines (x-1)/(-3)=(y-2)/(2k) =(z-3)/2 and (x-1)/(3k) =(y-5)/1=(z...

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  21. A line makes angles alpha,beta,gamma with the coordinates axes . If al...

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