To multiply these two terms you multiply each individual term in the left parenthesis by each individual term in the right parenthesis.
#(color(red)(3x^3) - color(red)(2x^2) - color(red)(2))(color(blue)(x^2) + color(blue)(x))# becomes:
#(color(red)(3x^3) xx color(blue)(x^2)) + (color(red)(3x^3) xx color(blue)(x)) - (color(red)(2x^2) xx color(blue)(x^2)) - (color(red)(2x^2) xx color(blue)(x)) - (color(red)(2) xx color(blue)(x^2)) - (color(red)(2) xx color(blue)(x))#
#3x^5 + 3x^4 - 2x^4 - 2x^3 - 2x^2 - 2x#
We can now combine like terms:
#3x^5 + (3 - 2)x^4 - 2x^3 - 2x^2 - 2x#
#3x^5 + 1x^4 - 2x^3 - 2x^2 - 2x#
#3x^5 + x^4 - 2x^3 - 2x^2 - 2x#
Or, if required, we can factor out an #x# term:
#x(3x^4 + x^3 - 2x^2 - 2x - 2)#
