Find a unit vector perpendicular to each of the vector  a&ra

Subject

Mathematics

Class

CBSE Class 12

Pre Boards

Practice to excel and get familiar with the paper pattern and the type of questions. Check you answers with answer keys provided.

Sample Papers

Download the PDF Sample Papers Free for off line practice and view the Solutions online.
Advertisement

 Multiple Choice QuestionsLong Answer Type

21.

Using elementary transformations, find the inverse of the matrx

 1 3  - 2- 3      0  - 121      0 


22.

Show that of all the rectangles inscribed in a given fixed circle, the square has the maximum area.


23.

Evaluate:  5 x + 3 x2 + 4 x + 10 dx


24.

Evaluate:  2x  x2 + 1   x2 + 3  dx


Advertisement
25.

Solve the following differential equation:

ex tan y dx + ( 1 - e) sec2 y dy  = 0


26.

Solve the following differential equation:

cos2 x dydx + y = tan x


Advertisement

27.

Find a unit vector perpendicular to each of the vector  a + b   and   a - b , where

  a = 3 i^ + 2 j^ + 2 k^   and    b =  i^ + 2 j^ - 2 k^.


a = 3 i^ + 2 j^ + 2 k^,     b =  i^ + 2 j^ - 2 k^. a  + b = 4 i^ + 4 j^       and      a  - b = 2 i^ + 4 k^   a  + b   x   a  - b  =  i^   j^  k^4    4      0 2     0     4  = i^  16  - j^  16  + k^  - 8                                           = 16 i^ - 16 j^ - 8 k^    a  + b   x   a  - b    =  162 + ( - 16 )2 + 64                                                      =  256 + 256 + 64                                                      =  576  = 24    

So, the unit vector, perpendicular to each of the vectors  a + b    and    a + b is given by

±   a + b  x  a - b   a + b  x  a - b   = ± 16 i^ - 16 j^ - 8 k^24=  ± 2 i^ - 2 j^ -  k^3 =  ± 2 i^3  23 j^   13 k^


Advertisement
28.

Find the angle between the following pair of lines:  

- x + 2- 2 = y - 17 = z + 3- 3   and   x + 2- 1 = 2 y - 84 = z - 54

And check whether the lines are parallel or perpendicular.


Advertisement
29.

Probabilities of solving problem independently by A and B are 12 and 13respectively. If both try to solve the problem independently, find the probability that

(i) the problem is solved

(ii) exactly one of them solves the problem.


30.

Using integration find the area of the triangular region whose sides have equations  y=2x+1,  y=3x+1  and  x=4.


Advertisement