English

Write the Ratio in Which Yz-plane Divides the Segment Joining P (−2, 5, 9) and Q (3, −2, 4).

Advertisements
Advertisements

Question

Write the ratio in which YZ-plane divides the segment joining P (−2, 5, 9) and Q (3, −2, 4).

Sum
Advertisements

Solution

\[ \text{ Let the YZ - plane divide the line segment joining points } P\left( - 2, 5, 9 \right) \text { and Q } \left( 3, - 2, 4 \right) \text{ in the ratio k: 1 } . \]

\[ \text{ Using the section formula, the coordinates of the point of intersection are given by }\]

\[\left( \frac{k\left( 3 \right) - 2}{k + 1}, \frac{k\left( - 2 \right) + 5}{k + 1}, \frac{k\left( 4 \right) + 9}{k + 1} \right)\]

\[ \text{ On the YZ - plane, the X - coordinate of any point is zero } . \]

\[ \therefore \frac{k\left( 3 \right) - 2}{k + 1} = 0\]

\[ \Rightarrow 3k - 2 = 0\]

\[ \Rightarrow k = \frac{2}{3}\]

\[ \text{ Thus, the YZ - plane divides the line segment formed by joining the given points in the ratio 2: 3 internally  } . \]

shaalaa.com
  Is there an error in this question or solution?
Chapter 26: Direction Cosines and Direction Ratios - Very Short Answers [Page 24]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 26 Direction Cosines and Direction Ratios
Very Short Answers | Q 7 | Page 24

RELATED QUESTIONS

Which of the following represents direction cosines of the line :

(a)`0,1/sqrt2,1/2`

(b)`0,-sqrt3/2,1/sqrt2`

(c)`0,sqrt3/2,1/2`

(d)`1/2,1/2,1/2`


Write the direction ratios of the following line :

`x = −3, (y−4)/3 =( 2 −z)/1`


If l, m, n are the direction cosines of a line, then prove that l2 + m2 + n2 = 1. Hence find the
direction angle of the line with the X axis which makes direction angles of 135° and 45° with Y and Z axes respectively.


Find the angle between the lines whose direction ratios are 4, –3, 5 and 3, 4, 5.


Find the direction cosines of a line which makes equal angles with the coordinate axes.


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


Find the direction cosines of the line passing through two points (−2, 4, −5) and (1, 2, 3) .


Find the angle between the vectors whose direction cosines are proportional to 2, 3, −6 and 3, −4, 5.


Show that the line through points (4, 7, 8) and (2, 3, 4) is parallel to the line through the points (−1, −2, 1) and (1, 2, 5).


Show that the line joining the origin to the point (2, 1, 1) is perpendicular to the line determined by the points (3, 5, −1) and (4, 3, −1).


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


What are the direction cosines of Y-axis?


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


Write the ratio in which the line segment joining (abc) and (−a, −c, −b) is divided by the xy-plane.


If a line has direction ratios proportional to 2, −1, −2, then what are its direction consines?


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

 


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


The xy-plane divides the line joining the points (−1, 3, 4) and (2, −5, 6)


The distance of the point P (abc) from the x-axis is 


The angle between the two diagonals of a cube is


 

 


If a line makes angles α, β, γ, δ with four diagonals of a cube, then cos2 α + cos2 β + cos2γ + cos2 δ is equal to


 Find the equation of the lines passing through the point (2, 1, 3) and perpendicular to the lines


If a line makes angles 90°, 135°, 45° with the x, y and z axes respectively, find its direction cosines.


Find the vector equation of a line passing through the point (2, 3, 2) and parallel to the line `vec("r") = (-2hat"i"+3hat"j") +lambda(2hat"i"-3hat"j"+6hat"k").`Also, find the distance between these two lines.


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

`1/sqrt(2), 1/2, 1/2`


Find the direction cosines of a vector whose direction ratios are
1, 2, 3


Find the direction cosines and direction ratios for the following vector

`5hat"i" - 3hat"j" - 48hat"k"`


Find the direction cosines and direction ratios for the following vector

`3hat"i" - 3hat"k" + 4hat"j"`


If `1/2, 1/sqrt(2), "a"` are the direction cosines of some vector, then find a


If a line makes angles α, β, γ with the positive directions of the coordinate axes, then the value of sin2α + sin2β + sin2γ is ______.


Find the equations of the two lines through the origin which intersect the line `(x - 3)/2 = (y - 3)/1 = z/1` at angles of `pi/3` each.


The Cartesian equation of a line AB is: `(2x - 1)/2 = (y + 2)/2 = (z - 3)/3`. Find the direction cosines of a line parallel to line AB.


The projections of a vector on the three coordinate axis are 6, –3, 2 respectively. The direction cosines of the vector are ______.


Find the coordinates of the image of the point (1, 6, 3) with respect to the line `vecr = (hatj + 2hatk) + λ(hati + 2hatj + 3hatk)`; where 'λ' is a scalar. Also, find the distance of the image from the y – axis.


If a line makes an angle α, β and γ with positive direction of the coordinate axes, then the value of sin2α + sin2β + sin2γ will be ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×