Question

Find the coefficient of x5 in (x+3)8

Answer 1

Answer:

1512

Step-by-step explanation:

It is known that ( R+1) th term $T_{r+1}$ in the binomial expansion of $(a+b)^{n}$ is given by $T_{r+1} = nC_{r} a^{n-r} b^{r}$

Assuming that x5 occurs in the (r + 1)th term of the expansion (x + 3)8, we obtain

Comparing the indices of x in x5 and in Tr +1, we obtain r = 3 Thus, the coefficient of x5 is 1512