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If, (1)/(""^(5)C(r ))+(1)/(""^(6)C(r ))=...

If, `(1)/(""^(5)C_(r ))+(1)/(""^(6)C_(r ))=(1)/(""^(4)C_(r ))`, then the value of r equals to

A

4

B

2

C

5

D

3

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WB JEE PREVIOUS YEAR PAPER-QUESTION PAPER 2016-MULTIPLE CHOICE QUESTIONS
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  2. The number of ways in which the letters of the word ARRANGE can be per...

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  3. If, (1)/(""^(5)C(r ))+(1)/(""^(6)C(r ))=(1)/(""^(4)C(r )), then the va...

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  4. For +ve integer n, n^(3)+2n is always divisible by

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  6. 1+""^(n)C(1)cos theta+""^(n)C(2)cos 2theta +…+""^(n)C(n) cos n theta e...

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  7. If x, y and z be greater than 1, then the value of |(1,log(x)y,log(x)z...

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  8. Let A is a 3xx3 matrix and B is its adjoint matrix. If |B|=64, then |A...

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  9. Let (("cos"(pi)/(4),-"sin"(pi)/(4)),("sin"(pi)/(4),"cos"(pi)/(4))) and...

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  13. Standard Deviation of n observations a(1), a(2), a(3),….a(n) is sigma....

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  14. Let A and B be two events such that P(A nn B)=(1)/(6),P(A uu B)=(31)/(...

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  15. The value of cos 15^(@)cos 7(1^(@))/(2)sin 7(1^(@))/(2) is

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  16. The smallest positive root of the equation tan x-x=0 lies in

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  17. If in a triangle ABC, AD, BE and CF are the altitudes and R is the cir...

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  18. The points (-a,-b),(a,b),(0,0) and (a^(2),ab), a ne 0, b ne 0 are alwa...

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  19. The line AB cuts off intercepts 2a from the axes. From any point. P on...

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  20. x+8y-22=0, 5x+2y-34=0, 2x-3y+13=0 are the three sides of a triangle. T...

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