Question

How do you use the binomial formula to find the coefficient of `p^(4)z^(19)` in the expansion of `(2p + z)^23`?

Answer 1

`32 ^(23)C_4`

Explanation:

In the expansion of `(x+y)^n`, r+1 th term is `T_(r+1)= ^n C_r x^r y^(n-r)`.

Taking r=4, n=23, the fifth term would be `=^23C_4 32p^4z^19`.

The coefficient of `p^4 z^19` would be `32 ^(23)C_4`