हिंदी
तमिलनाडु बोर्ड ऑफ सेकेंडरी एज्युकेशनएचएससी विज्ञान कक्षा ११

Find the direction cosines and direction ratios for the following vector ijk3i^-4j^+8k^

Advertisements
Advertisements

प्रश्न

Find the direction cosines and direction ratios for the following vector

`3hat"i" - 4hat"j" + 8hat"k"`

योग
Advertisements

उत्तर

The direction ratios of the `3hat"i" - 4hat"j" + 8hat"k"` are (3, – 4, 8)

The direction cosines of the vector `3hat"i" - 4hat"j" + 8hat"k"` are 

`3/sqrt(3^2 + (-4)^2 + 8^2),(-4)/sqrt(3^2 + (-4)^2 + 8^2), 8/sqrt(3^2 + (-4)^2 + 8^2)`

`3/sqrt(9 + 16 + 64), (-4)/sqrt(9 + 16 + 64), 8/sqrt(9 + 16 + 64)`

`(3/sqrt(89), (-4)/sqrt(89), 8/sqrt(89))`

Direction ratios = (3, – 4, 8)

Direction cosines = `(3/sqrt(89), (-4)/sqrt(89), 8/sqrt(89))`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Vector Algebra - Exercise 8.2 [पृष्ठ ६८]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 8 Vector Algebra
Exercise 8.2 | Q 3. (i) | पृष्ठ ६८

संबंधित प्रश्न

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.........


If a line makes angles 90°, 135°, 45° with the X, Y, and Z axes respectively, then its direction cosines are _______.

(A) `0,1/sqrt2,-1/sqrt2`

(B) `0,-1/sqrt2,-1/sqrt2`

(C) `1,1/sqrt2,1/sqrt2`

(D) `0,-1/sqrt2,1/sqrt2`


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


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


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


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).


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


A line makes an angle of 60° with each of X-axis and Y-axis. Find the acute angle made by the line with Z-axis.


Write direction cosines of a line parallel to z-axis.


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


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


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

`4/3, 0, 3/4`


If a line makes an angle of 30°, 60°, 90° with the positive direction of x, y, z-axes, respectively, then find its direction cosines.


O is the origin and A is (a, b, c). Find the direction cosines of the line OA and the equation of plane through A at right angle to OA.


If a line has the direction ratio – 18, 12, – 4, then what are its direction cosine.


If a line makes angles of 90°, 135° and 45° with the x, y and z axes respectively, then its direction cosines 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 \[\alpha\], \[\beta\], and \[\gamma\] are the direction angles of a line, which ordered triple gives its direction cosines?


A line passes through \[P(x_1,y_1,z_1)\] and \[Q(x_2,y_2,z_2)\]. Which is one set of direction ratios of the line?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×