Question

当x=负4 y=2求代数式负3x的2次方y伽3xy2次方伽x的3次方伽3x的2次方y减负3xy的2次方减y的`3次方的值

Answer 1

-3x^2Y+3XY^2+X^3+3X^2Y-(-3XY^2)-Y^3

=6XY^2+X^3-Y^3

=Y^2(6X-Y)+X^3 x=-4 y=2

=2^2(-4*6-2)+(-4)^3

=-104-64

=-170