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