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The number of selection of n objects fro...

The number of selection of n objects from 2n objects of which n are identical and the rest are different is

A

`2^(n)`

B

`2^(n-1)`

C

`2^(n)-1`

D

`2^(n-1) + 1`

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WB JEE PREVIOUS YEAR PAPER-QUESTION PAPER 2018-MULTIPLE CHOICE QUESTIONS
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  2. If b(1) b(2)= 2(c(1) +c(2))and b(1), b(2), c(1), c(2) are all real num...

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  3. The number of selection of n objects from 2n objects of which n are id...

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  4. Let A be the centre of the circle x^(2) + y^(2)-2x-4y -20 = 0. Let B(1...

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  5. Let f(x) {(-2 sin x,"if " x le - (pi)/(2)),(A sin x + B," if " -(pi)/(...

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  6. The normals to the curve y= x^(2)-x +1, drawn at the points with the a...

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  7. The equation x log x= 3- x

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  8. Consider the parabola y^(2)= 4x. Let P and Q be points on the parabola...

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  9. A ladder 20 ft long leans against a vertical wall. The top end slides ...

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  10. For 0 le p le 1 and for any positive a, b, let I(p)= (a + b)^(p), J(p)...

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  11. Let vec(alpha)= hat(i)+ hat(j) + hat(k), vec(beta) = hat(i) - hat(j)- ...

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  12. Let vec(alpha), vec(beta), vec(gamma) be three unit vectors such that ...

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  13. Let z(1) and z(2) be complex numbers such that z(1) ne z(2) and |z(1)|...

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  14. From a collection of 20 consecutive natural numbers, four are selected...

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  15. The least positive integer n such that (("cos"(pi)/(4),"sin"(pi)/(4)),...

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  16. Let rho be a relation defined on 11, the set of natural numbers, as rh...

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  17. If the polynomial f(x)= |((1+x)^(a),(2+x)^(b),1),(1,(1+x)^(a),(2+x)^(b...

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  18. A line cuts the x-axis at A(5,0) and the y-axis at B(0, -3). A variabl...

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  19. In a third order matrix A, a(ij) denotes the elements in the i-th row ...

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  20. The area of the triangle formed by the intersection of a line parallel...

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