Question

What if the coefficient of x^6y^4 in the expansion of (x+y)^10

A.) 1
B.) 5
C.) 210
D.) It does not exist.

Answer 1

C..............................................

Answer 2

C) 210

Explanation:

Using binomial expansion for

`(x+y)^10`

we have general term

`T_(r+1) =10Cr x^(10-r) y^r,r=0,1,2,3....10`

Now we want the term which has 10-r =6 or r =4

Hence coefficient would be

10C4

=
`(10(9)(8)(7))/(1(2)(3)(4)) \\=210`

Hence answer is option C

210