Formula for Coefficients in a Trinomial Expansions is
\frac{n!}{r!}
n = power of the given expansion = 8
r = power of the asked coefficient
here it is asked for the coefficient of wx^{3}y^{2}z^{2}
their powers
w=1, x=3, y=2, z=2
so r = 1!* 3! * 2!* 2!
\Rightarrow\frac{8!}{1!* 3!*2!* 2!}
= 1680
\therefore coefficient of wx^{3}y^{2}z^{2} is 1680
Determine the coefficient of
wx^3y^2z^2 in (2w−x+y−2z)^8
1 answer