When (x + 2y - z)^8 is expanded, and the like terms are combined, what is the coefficient of the term x^3*y^3*z^2?
[ ( x + 2y) - z)^8
The constant will be from the expansion of
C( 8 , 2) [(x + 2y) ]^6 * z^2 =
C(8,2) * C( 6,3) (x^3) (2y)^3 * z^2 =
28 * 20 * 2^3 * x^3 * y^3 * z^2 =
28 * 20 * 8 * x^3 y^3 z^2 =
4480 x^3 y^3 z^2
