Home
Class 12
MATHS
Prove that ^n C0^(2n)Cn-^n C1^(2n-1)Cn+^...

Prove that `^n C_0^(2n)C_n-^n C_1^(2n-1)C_n+^n C_2xx^(2n-2)C_n++(-1)^n^n C_n^n C_n=1.`

Text Solution

Verified by Experts

We know that
`.^(2n)C_(n) =` Coefficient of `x^(n)` in `(1+x)^(2n)`
`.^(2n-1)C_(n) =` Coefficient of `x^(n)` in `(1+x)^(2n-1)`
`.^(2n-2)C_(n) =` Coefficient of `x^(n)` in `(1+x)^(2n-2)`
`.^(2n-3)C_(n) =` Coefficient of `x^(n)` in `(1+x)^(2n-3)`
`.^(n)C_(n) =` Coefficient of `x^(n)` in `(1+x)^(n)`
Thus, we have
`.^(n)C_(0).^(2n)C_(n)-.^(n)C_(1).^(2n-1)C_(n)+.^(n)C_(2).^(2n-2)C_(n)+"...."+(-1)^(n).^(n)C_(n).^(n)C_(n)`
= Coefficient of `x^(n)` in `[C_(0)(1+x)^(2n)-C_(1)(1+x)^(2n-1)+C_(2)(1+x)^(2n-2)-C_(3)(1+x)^(2n-3)+"...."+(-1)^(n)C_(n)(1+x)^(n)]`
`=` Coefficient of `x^(m)` in `(1+x)^(n)[C_(0)(1+x)^(n)-C_(1)(1+x)^(n-1)+C_(2)(1+x)^(n-2)-C_(3)(1+x)^(n-3)+"......"+(-1)^(n)C_(n)]`
`=` Coefficient of `x^(n)` in `(1+x)^(n)[(1+x)-1]^(n)`
`=` Coefficient of `x^(n)` in `(1+x)^(n)x^(n)`
`= 1`
Promotional Banner

Topper's Solved these Questions

  • BINOMIAL THEOREM

    CENGAGE|Exercise Exercise 8.1|17 Videos
  • BINOMIAL THEOREM

    CENGAGE|Exercise Exercise 8.2|10 Videos
  • AREA UNDER CURVES

    CENGAGE|Exercise Question Bank|20 Videos
  • BINOMIAL THEORM

    CENGAGE|Exercise Question Bank|31 Videos

Similar Questions

Explore conceptually related problems

Prove that ^nC_(0)^(2n)C_(n)-^(n)C_(1)^(2n-1)C_(n)+^(n)C_(2)xx^(2n-2)C_(n)++(-1)^(n)sim nC_(n)^(n)C_(n)=1

Prove that ^nC_(0)^(2n)C_(n)-^(n)C_(1)^(2n-2)C_(n)+^(n)C_(2)^(2n-4)C_(n)-...=2^(n)

Prove that (^(2n)C_0)^2+(^(2n)C_1)^2+(^(2n)C_2)^2-+(^(2n)C_(2n))^2-(-1)^n^(2n)C_ndot

Prove that ^nC_(0)^(n)C_(0)-^(n+1)C_(1)^(n)C_(1)+^(n+2)C_(2)^(n)C_(2)-...=(-1)^(n)

If (1 + x)^(n) = C_(0) + C_(1) x + C_(2) x^(2) + …+ C_(n) x^(n) , prove that C_(0) C_(n) - C_(1) C_(n-1) + C_(2) C_(n-2) - …+ (-1)^(n) C_(n) C_(0) = 0 or (-1)^(n//2) (n!)/((n//2)!(n//2)!) , according as n is odd or even .

Prove that C_(0)^(2)+C_(1)^(2)+...C_(n)^(2)=(2n!)/(n!n!)

Prove that C_(1)^(2)-2*C_(2)^(2)+3*C_(3)^(2)-…-2n*C_(2n)^(2)=(-1)^(n)n*C_(n)

If (1 + x)^(n) = C_(0) + C_(1) x + C_(2) x^(2) + …+ C_(n) x^(n) , prove that C_(0)^(2) - C_(1)^(2) + C_(2)^(2) -…+ (-1)^(n) *C_(n)^(2)= 0 or (-1)^(n//2) * (n!)/((n//2)! (n//2)!) , according as n is odd or even Also , evaluate C_(0)^(2) + C_(1)^(2) + C_(2)^(2) - ...+ (-1)^(n) *C_(n)^(2) for n = 10 and n= 11 .

Prove that : ""^(n)C_(0).""^(2n)C_(n)-""^(n)C_(1).""^(2n-2)Cn_(n)+""^(n)C_(2).""^(2n-4)Cn_(n)+......=2^n

prove that C_(0)C_(n)+C_(1)C_(n-1)+C_(2)C_(n-2)+.........+C_(n)C_(0)=2nC_(n)