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GUYS IF YOU WANT GRACE MARKS IN MATHEMATICS THEN PLEASE SIGN THIS PETITION....
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Will cbse make me paas in maths paper of class 12 session 201617 will i get grace marks if i am getting 23 out of 100 ..
Will the checking lenient??

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tan^{1 }x3/x4. +. tan^{1} x+3/x+4. =. π/4

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I think it is x2 and x +2 instead of x3 and x +3 respectively
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{tex}tan^{1} ({x2\over x4})+ tan^{1}( {x+2\over x+4}) = {\pi \over 4}{/tex}
Using{tex}tan^{1} x + tan^{1}y = tan^{1} ({x+y\over 1xy}){/tex}
=> {tex}tan^{1} ({{x2\over x4} + {x+2\over x+4}\over 1( {x2\over x4} \times {x+2\over x+4})}) = {\pi \over 4}{/tex}
=> {tex}tan^{1}({2x^216\over 12}) = {\pi \over 4}{/tex}
{tex}=> {2x^216\over 12}= tan^{1} {\pi \over 4}{/tex}
{tex}=> {2x^216\over 12}= 1{/tex}
{tex}=> 2x^216= 12{/tex}
{tex}=> 2x^2= 4 => x^2 = 2{/tex}
{tex}x = \sqrt 2{/tex}
if you use 3 answer ll be {tex}x = \sqrt {17\over 2}{/tex}
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Find the matrix A such that
Matrix of ( 2. 1. (1. 8
1. 0. * A=. 1. 2
3. 4) 9. 22)

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There are 4 cards numbered 1,3,5and 7 one number on one card . Two cards are drawn at random! Without replacement . Let x denote the sum of the numbers on the two cards .Find the mean and variance of x

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Find the value of x such that the points are coplanar A(3,2,1), B(4,x,5),. C(4,2,2) and D(6,5,1)

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Ans.
Points are A(3,2,1), B(4,x,5), C(4,2,2) And D(6,5,1).
Position Vector of A = {tex}3\hat i + 2\hat j + \hat k{/tex}
Position Vector of B = {tex}4\hat i + x\hat j + 5\hat k{/tex}
Position Vector of C = {tex}4\hat i + 2\hat j 2\hat k{/tex}
Position Vector of D = {tex}6\hat i + 5\hat j \hat k{/tex}
{tex}=> \overrightarrow {AB} = \hat i + (2x)\hat j + 4\hat k{/tex}
{tex}=> \overrightarrow {AC} = \hat i + 0\hat j 3\hat k{/tex}
{tex}=> \overrightarrow {AD} = 3\hat i + 3\hat j 2\hat k{/tex}
As points are coplaner, then triple scaler product is zero,
So,
{tex}\begin{bmatrix} 1& (x2) & 4 \\[0.3em] 1 & 0 & 3 \\[0.3em] 3 & 3 & 2 \end{bmatrix} = 0{/tex}
Expanding along R_{2}
=> 1[2(x2) 12] (3)[33(x2)] = 0
=> 2x 4+12 +99x +18 = 0
=> 7x +35 = 0
=> 7x = 35
=> x = 5
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Using the method of integration find the area of the triangle ABC , coordinates of whose vertices are A(4,1). B(6,6),. C(8,4)

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Find the coordinates of the point where the line through the points (3,4,5)and (2,3,1),crosses the plane determined by the points (1,2,3),(4,2,3)and (0,4,3).

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(1,2,7)
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Will teachers will do linent marking or strict marking in mathematics

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What is the minimum passing marks required for mathematics in class12?

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33% marks are required to pass any subject.
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find the area enclosed between the parabola 4y= 3x^{2 and the straight line 3x 2y+12=0}

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how will be the evalution of maths examination conducted today be?

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integration of sin inverse x divide by x

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For what value of k ,the system of linear equatoin
X+y+z=2
2x+yz=3
3x+2y+kz=4

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Important. Question given by u r from ncert only?

Are most of the questions given tomorrow in the exam are from ncert examples?
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Yeah......it is for sure.but dont depend on it fullt.practice other problems also.
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Find the shortest distance between the line xy+1=0 and thr curve y^{2}= x

pls teachers answer it quickly i really need ur help
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A signal which can be green or red with probability 4/5 and 1/5 respectivEly, is received by station A and then transmitted to station B. The probability of each receiving the signal correctly is 3/4. If the signal received at station B is green, then find the probability that original signal is green.

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3 no.s are selected at random from first 6 +ve integers. x denotes the smallest of 3 no.s selected . find the probabiloty distribution of x?

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How many marks are allotted to questions on 3D geometry?

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One 6 marks question will surely come
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The probablity of specific problems being solved independently by A and B are 1/2 and 1/3 respectively. If both tried to solve the problem independently find the probablity of
1. Both of them solved
2. None of them solve
3. The problem is solved

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i) 2/3
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if A=
1  2 
3  5 
then find the value of A^20095A^2008

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Shall I be able to print those sample paper I brought?

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in a town there are 486 families having 6 children each . if probability of survival of a girl is 1/3 and that of boy is 2/3 . find the number of families having 2 girls and 4 boys

does this ques belong to 12 class or somehow 9 too?
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a die is loaded in such a way that the probabilities of getting an even number is twice as likely to occur as an odd number.if the fire is tossed twice find the probability distribution of the random variable representing the number as a prime number in the two tosses

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Is (A')^{1} = (A^{1})'

so what??

U is also called universal set.
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But the question is from matrices and determinants
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A' is a set for UA
thus (A')^{1 }is a set for 1/(UA)
A^{1}=1/A and thus( A^{1})' is a set for (U1/A)
SINCE both values are not same therefore (A')^{1} not equals to (A^{1}).
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There are two identical bags .bag 1 contain 3red and 4black balls while bag 2 contain 5 red and 4 black balls.one ball is drawn at random from one of the bags .find the probability that ball drawn is red.

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62/63
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^{16/3}
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In a hockey match ,both teams A and B scored same number of goals upto the end of the match so to decide the winner the referee asked both the captain's to throw a dielectric alternatively and decide that the team ,whose captain gets first six ,will be declared as the winner .If the captain team A starts find the probability of winning match

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Ans. Let the probability that A gets a six is 1/6.
Hence, p = 1/6 and q = 1 1/6 = 5/6
Probability of A's Winning =
{tex}P(A) + P(\overline A \space \overline B A) +P(\overline A \space \overline B \space \overline A \space \overline B A) +…………{/tex}
=> p + pq^{2} + pq^{4} +………………
This is in geometric progression, where sum is
{tex}S_n = {p\over 1q^2}{/tex}
Substituing Value for p and q,
{tex}=> {{1\over 6}\over {1({5\over 6})^2}} {/tex}
{tex}=> {{1\over 6}\over {1{25\over 36}}} => {{1\over 6}\over {11\over 36}}{/tex}
Probability of A's winning = 6/11
Probability of B's winning = 16/11 = 5/11
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please tell me those questions, which have chance in exam of maths?
you can also give me question number along with page number of ncert book.

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