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If the edges of a rectangular parallelop...

If the edges of a rectangular parallelopiped are a, b and c, show that the angles between the four diagonals are given by `cos^-1frac{a^2+-b^2+-c^2}{a^2+b^2+c^2}`

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MODERN PUBLICATION-Three Dimensional Geometry-EXERCISE
  1. Find the projection of the line segment joining the points: (2,-3,0), ...

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  2. Find the projection of the line segment joining the points (1,2,3), (4...

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  3. If the edges of a rectangular parallelopiped are a, b and c, show that...

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  4. write the vectoe equation of the line : (x-5)/-3=(y+4)/7=(6-z)/2.

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  5. show that the three lines with direction cosines <12/13,-3/13,-4/13>, ...

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  6. express the following equations of the lines into vector form: (x-3)/3...

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  7. Find the cartesian equation of the line which passes through the point...

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  8. Find the cartesian as well as the vector equation of the line passing ...

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  9. Find the cartesian as well as the vector equation of the line passing ...

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  10. The cartesian equations of a line are : (x-5)/3=(y+4)/7=(z-6)/2 and (x...

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  11. Find the equation of a line parallel to x-axis and passing through the...

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  12. Find the direction cosines of a line parallel to the line :(x-5)/6=(y+...

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  13. Write the direction cosine of a line parallel to the line : (3-x)/3=(y...

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  14. Find the vector and the Cartesian equations of the line through the po...

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  15. Find the equation of the line passing through the point (2, -1, 3) and...

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  16. Find the equation of the line in vector and in cartesian form that pas...

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  17. Find the vector equation for the line through the points : (1,2,2) and...

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  18. Find the vector and the cartesian equations of the lines that passes t...

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  19. Find the vector and cartesian equations of the line that passes throug...

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  20. Find the equation of a st line through (-1,2,3) and equally inclined t...

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