The expression of the volume of the box with dimensions of
(3x+1) by (2x-1) by (x+2) will be:
volume, V=lwh
plugging the values we get:
V=(3x+1)(2x-1)(x+2)
Expanding the above we get:
V=(3x+1)(2x^2+3x-2)
V=3x(2x^2+3x-2)+1(2x^2+3x-2)
V=6x^3+9x^2-6x+2x^2+3x-2
V=6x^3+11x^2-3x-2
Hence the expression for the volume will be:
V=6x^3+11x^2-3x-2