English

A Parallelopiped is Formed by Planes Drawn Through the Points (2, 3, 5) and (5, 9, 7), Parallel to the Coordinate Planes. the Length of Diagonal of the Parallelopiped is (A) 7 `Sqrt(38)` `Sqrt(155)`

Advertisements
Advertisements

Question

A parallelopiped is formed by planes drawn through the points (2, 3, 5) and (5, 9, 7), parallel to the coordinate planes. The length of a diagonal of the parallelopiped is

Options

  • 7

  • `sqrt(38)`

  • `sqrt(155)`

  • none of these

MCQ
Advertisements

Solution

7  

\[\text{ The given points } \left( 2, 3, 5 \right) \text{ and } \left( 5, 9, 7 \right) \text{ are two diagonally opposite vertices of the parallelopiped as all of their coordinates are different }. \]

\[ \therefore \text{ Edges of the parallelopiped } = \left| 2 - 5 \right|, \left| 3 - 9 \right| \text{ and } \left| 5 - 7 \right| \]

\[ = 3, 6 \text{ and } 2\]

\[\text { Now} , \]

\[\text{ Length of the diagonal of the parallelopiped } = \sqrt{\left( 3 \right)^2 + \left( 6 \right)^2 + \left( 2 \right)^2}\]

\[ \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} = \sqrt{9 + 36 + 4}\]

\[ \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} = \sqrt{49} \]

\[ \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} \hspace{0.167em} = 7\]

\[\text{ Hence, length of the diagonal of the parallelopiped formed by the planes parallel to coordinate planes and drawn through points }  \left( 2, 3, 5 \right) \text { and }  \left( 5, 9, 7 \right) \text{ is 7 units } . \]

 

shaalaa.com
  Is there an error in this question or solution?
Chapter 26: Direction Cosines and Direction Ratios - MCQ [Page 25]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 26 Direction Cosines and Direction Ratios
MCQ | Q 4 | Page 25

RELATED QUESTIONS

Find the direction cosines of the line perpendicular to the lines whose direction ratios are -2, 1,-1 and -3, - 4, 1 


Direction cosines of the line passing through the points A (- 4, 2, 3) and B (1, 3, -2) are.........


Write the direction ratios of the following line :

`x = −3, (y−4)/3 =( 2 −z)/1`


Find the direction cosines of the sides of the triangle whose vertices are (3, 5, −4), (−1, 1, 2) and (−5, −5, −2).


Find the angle between the vectors with direction ratios proportional to 1, −2, 1 and 4, 3, 2.


Show that the points (2, 3, 4), (−1, −2, 1), (5, 8, 7) are collinear.


Find the angle between the lines whose direction ratios are proportional to abc and b − cc − aa− b.


Find the direction cosines of the lines, connected by the relations: l + m +n = 0 and 2lm + 2ln − mn= 0.


Find the angle between the lines whose direction cosines are given by the equations
(i) m + n = 0 and l2 + m2 − n2 = 0


Find the angle between the lines whose direction cosines are given by the equations

2l − m + 2n = 0 and mn + nl + lm = 0


Find the angle between the lines whose direction cosines are given by the equations

 l + 2m + 3n = 0 and 3lm − 4ln + mn = 0


What are the direction cosines of Z-axis?


Write the distances of the point (7, −2, 3) from XYYZ and XZ-planes.


Write the distance of the point (3, −5, 12) from X-axis?


Write the inclination of a line with Z-axis, if its direction ratios are proportional to 0, 1, −1.


Write the angle between the lines whose direction ratios are proportional to 1, −2, 1 and 4, 3, 2.


Write the distance of the point P (xyz) from XOY plane.


Write the coordinates of the projection of point P (xyz) on XOZ-plane.


If a unit vector  `vec a` makes an angle \[\frac{\pi}{3} \text{ with } \hat{i} , \frac{\pi}{4} \text{ with }  \hat{j}\] and an acute angle θ with \[\hat{ k} \] ,then find the value of θ.


For every point P (xyz) on the xy-plane,

 


If the x-coordinate of a point P on the join of Q (2, 2, 1) and R (5, 1, −2) is 4, then its z-coordinate is


Verify whether the following ratios are direction cosines of some vector or not

`1/5, 3/5, 4/5`


Verify whether the following ratios are direction cosines of some vector or not

`4/3, 0, 3/4`


Find the direction cosines of a vector whose direction ratios are
0, 0, 7


If `vec"a" = 2hat"i" + 3hat"j" - 4hat"k", vec"b" = 3hat"i" - 4hat"j" - 5hat"k"`, and `vec"c" = -3hat"i" + 2hat"j" + 3hat"k"`,  find the magnitude and direction cosines of `3vec"a"- 2vec"b"+ 5vec"c"`


Find the direction cosines of the line passing through the points P(2, 3, 5) and Q(–1, 2, 4).


If α, β, γ are the angles that a line makes with the positive direction of x, y, z axis, respectively, then the direction cosines of the line are ______.


If a variable line in two adjacent positions has direction cosines l, m, n and l + δl, m + δm, n + δn, show that the small angle δθ between the two positions is given by δθ2 = δl2 + δm2 + δn


If the directions cosines of a line are k,k,k, then ______.


The line `vec"r" = 2hat"i" - 3hat"j" - hat"k" + lambda(hat"i" - hat"j" + 2hat"k")` lies in the plane `vec"r".(3hat"i" + hat"j" - hat"k") + 2` = 0.


Find the direction cosine of a line which makes equal angle with coordinate axes.


If two straight lines whose direction cosines are given by the relations l + m – n = 0, 3l2 + m2 + cnl = 0 are parallel, then the positive value of c is ______.


Equation of line passing through origin and making 30°, 60° and 90° with x, y, z axes respectively, is ______.


If the equation of a line is x = ay + b, z = cy + d, then find the direction ratios of the line and a point on the line.


Find the coordinates of the foot of the perpendicular drawn from point (5, 7, 3) to the line `(x - 15)/3 = (y - 29)/8 = (z - 5)/-5`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×