# Write the general term in the expansion of    Q4.    $(x^2 - xy)^{12}, \ x\neq 0$

As we know that the general  $(r+1)^{th}$ term  $T_{r+1}$ in the binomial expansion of  $(a+b)^n$  is given by
$T_{r+1}=^nC_ra^{n-r}b^r$
So the general term of the expansion of $(x^2 - xy)^{12},$ is
$\\\Rightarrow T_{r+1}\\=^{12}C_r(x^2)^{12-r}(-xy)^r\\=(-1)^r\times^{12}C_rx^{24-2r+r}y^r\\=(-1)^r\times^{12}C_rx^{24-r}y^r$.