English
Tamil Nadu Board of Secondary EducationHSC Science Class 11

Find the direction cosines and direction ratios for the following vector ijk3i^+j^+k^ - Mathematics

Advertisements
Advertisements

Question

Find the direction cosines and direction ratios for the following vector

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

Sum

Solution

The direction ratios of the vector `3hat"i" + hat"j" + hat"k"` are (3, 1, 1)

The direction cosines of the vector `3hat"i" + hat"j" + hat"k"` are

`3/sqrt(3^2 + 1^2 + 1^2), 1/sqrt(3^2 + 1^2 + 1^2), 1/sqrt(3^2 + 1^2 + 1^2)`

`3/sqrt(9 + 1 + ), 1/sqrt(9 + 1 + 1), 1/sqrt(9 + 1 + 1)`

`(3/sqrt(11), 1/sqrt(11), 1/sqrt11)`

Direction ratios = (3, 1, 1)

Direction cosines = `(3/sqrt(11), 1/sqrt(11), 1/sqrt11)`

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Vector Algebra - Exercise 8.2 [Page 68]

APPEARS IN

Samacheer Kalvi Mathematics - Volume 1 and 2 [English] Class 11 TN Board
Chapter 8 Vector Algebra
Exercise 8.2 | Q 3. (ii) | Page 68

RELATED QUESTIONS

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


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


Find the Direction Cosines of the Sides of the triangle Whose Vertices Are (3, 5, -4), (-1, 1, 2) and (-5, -5, -2).


If a line makes angles of 90°, 60° and 30° with the positive direction of xy, and z-axis respectively, find its direction cosines


What are the direction cosines of Y-axis?


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


The angle between the two diagonals of a cube is


 

 


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


Find the direction cosines and direction ratios for the following vector

`hat"j"`


Choose the correct alternative:
The unit vector parallel to the resultant of the vectors `hat"i" + hat"j" - hat"k"` and `hat"i" - 2hat"j" + hat"k"` is


If the direction ratios of a line are 1, 1, 2, find the direction cosines of the line.


The x-coordinate of a point on the line joining the points Q(2, 2, 1) and R(5, 1, –2) is 4. Find its z-coordinate.


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


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


The area of the quadrilateral ABCD, where A(0,4,1), B(2, 3, –1), C(4, 5, 0) and D(2, 6, 2), is equal to ______.


If a line makes angles 90°, 135°, 45° with x, y and z-axis respectively then which of the following will be its direction cosine.


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.


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×