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

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 Multiple Choice QuestionsShort Answer Type

21.

The scalar product of the vector straight a with rightwards arrow on top equals space straight i with hat on top plus straight j with hat on top plus straight k with hat on top with a unit vector along the sum of vectors straight b with rightwards arrow on top equals 2 straight i with hat on top plus 4 straight j with hat on top minus 5 straight k with hat on top space space and space straight c with rightwards arrow on top space equals space straight lambda straight i with hat on top plus 2 straight j with hat on top plus 3 straight k with hat on top is equal to one. Find the value of straight lambda and hence find the unit vector along straight b with rightwards arrow on top plus straight c with rightwards arrow on top.

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22. Evaluate colon
integral subscript 0 superscript straight pi fraction numerator 4 straight x space sinx over denominator 1 plus cos squared straight x end fraction dx
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23.

Evaluate:
integral fraction numerator straight x plus 2 over denominator square root of straight x squared plus 5 straight x plus 6 end root end fraction dx

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24.

An experiment succeeds thrice as often as it fails. Find the probability that in the next five trials, there will be at least 3 successes.

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25. If space straight y space equals space Pe to the power of ax plus Qe to the power of bx show that
straight d to the power of 2 straight y end exponent over dx squared minus left parenthesis straight a plus straight b right parenthesis dy over dx plus aby space equals 0
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26. If space straight x equals cost left parenthesis 3 minus 2 cos squared straight t right parenthesis space and space straight y equals sint left parenthesis 3 minus 2 sin squared straight t right parenthesis comma space find space the space value space of space dy over dx at space straight t equals straight pi over 4.
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27.

Find the particular solution of the differential equation log open parentheses dy over dx close parentheses equals 3 straight x plus 4 straight y comma space given space that space straight y space equals space 0 comma space when space straight x equals space 0.

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28.

Find the value of p, so that the lines:
are perpendicular to each other. Also find the equations of a line passing through a point (3, 2, -4) and parallel to line l1.

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 Multiple Choice QuestionsLong Answer Type

29.

Find the equation of the plane through the line of intersection of the planes x + y + z = 1 and 2x + 3y + 4z = 5 which is perpendicular to the plane x- y + z = 0. Also find the distance of the plane obtained above, from the origin.

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30.

Find the distance of the point (2, 12, 5) from the point of intersection of the line 
straight r with rightwards arrow on top equals 2 straight i with hat on top minus 4 straight j with hat on top plus 2 straight k with hat on top plus straight lambda open parentheses 3 straight i with hat on top plus 4 straight j with hat on top plus 2 straight k with hat on top close parentheses space and space the space plane space straight r with rightwards arrow on top. open parentheses straight i with hat on top minus 2 straight j with hat on top plus straight k with hat on top close parentheses equals 0.


Any point in the line is
2 plus 3 straight lambda comma space minus 4 plus 4 straight lambda comma space space 2 plus 2 straight lambda
The vector equation of the plane is given as

straight r with rightwards arrow on top. space open parentheses straight i with hat on top minus 2 straight j close parentheses plus straight k right parenthesis space equals space 0
Thus space the space cartesian space equation space of space the space plane space is space straight x minus 2 straight y plus straight z equals space 0
Since space the space point space lies space in space the space plane
left parenthesis 2 plus 3 straight lambda right parenthesis 1 plus left parenthesis negative 4 plus 4 straight lambda right parenthesis thin space left parenthesis negative 2 right parenthesis plus left parenthesis 2 plus 2 straight lambda right parenthesis 1 space equals 0
rightwards double arrow space 2 plus 8 plus 2 plus 3 straight lambda minus 8 straight lambda plus 2 straight lambda equals 0
rightwards double arrow 12 minus 3 straight lambda equals 0
rightwards double arrow 12 equals space 3 straight lambda
rightwards double arrow straight lambda equals 4

Thus, the point of intersection of the line and the plane is:
2 plus 3 cross times 4 comma space minus 4 plus 4 cross times 4 comma space space 2 plus 2 cross times 4
rightwards double arrow 14 comma space 12 comma space 10
Distance between (2, 12, 5) and (14, 12, 10) is:
straight d equals square root of left parenthesis 14 minus 2 right parenthesis squared plus left parenthesis 12 minus 12 right parenthesis squared plus left parenthesis 10 minus 5 right parenthesis squared end root
rightwards double arrow straight d equals space square root of 144 plus 25 end root
rightwards double arrow space straight d equals square root of 169
rightwards double arrow straight d space equals space 13 space units

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