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nCr+^nC(r+1)=^(n+1)Cx, then x is equal t...

`nC_r+^nC_(r+1)=^(n+1)C_x`, then x is equal to:

A

2r

B

`(r-1)/2`

C

r+1

D

none of these

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JBD PUBLICATION-MODEL PAPER (15)-EXERCISE
  1. The solutions of the equation sin^2x+3sinx=0 is:

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  2. The value of (2+sqrt(3))(2-sqrt(3)) is:

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  3. nCr+^nC(r+1)=^(n+1)Cx, then x is equal to:

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  4. The nth term of a G.P. is 128 and the sum of its n terms is 225. If it...

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  5. The three striaght lines ax+by=c, bx+cy=a and cx+ay=b are collinear if...

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  6. If the circle x^2+y^2+2ax+8y+16=0 touches x axis, then the vlaue of a ...

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  7. In a single toss of three coins, the probability of getting head and t...

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  8. Prove that:(sinx +sin3x)/(cosx+cos3x)=tan2x

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  9. Prove that (sin(x+y))/(sin(x-y))=(tanx+tany)/(tanx-tany)

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  10. If z1= 2 -i, z2= 1+ i, find |(z1+z2+1)/(z1-z2+1)|.

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  11. Show that 9^(n+1) - 8n -9 is divisible by 64, whenever n is a positiv...

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  12. Compute (98)^5

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  13. Using distance formula, show that the points A(6,-7,1), B(2,-3,1) and ...

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  14. Show that the statement is true by the method of contradiction. If x i...

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  15. Find the component statement of the following and check whether they a...

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  16. Prove that A^c-B^c=B-A.

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  17. If f(x)=log(x/(x-1)), show that f(x+1)+f(x)=log ((x+1)/(x-1))

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  18. Prove that:cos15^@-sin15^@=1/sqrt2

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  19. Prove that : cos 24^@+ cos 55^@ + cos 125^@ + cos204^@ + cos 300^@= 1/...

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  20. How many words, with or without meaning, each of 2 vowels and 3 conson...

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