What is the standard form of #y=(3-x)(5x^2-2x)#?

1 Answer
Jan 1, 2016

#y = -5x^3 +17x^2 -6x#

Explanation:

We just have to multiply the numbers inside the parenthesis. First, the first number in the first parenthesis multiplied by each number in the second one:
#3 * 5x^2 + 3 * (-2x) = 15x^2 - 6x#

And now, the same thing: the second number in the first parenthesis multiplied by each number in the second one:
#(-x) * 5x^2 + (-x) * (-2x) = -5x^3 + 2x^2#

Then, we just put them together and order them in the cubic function standard form(#y = Ax^3 + Bx^2 +Cx +D#):
#y = 15x^2 - 6x + -5x^3 + 2x^2#
#y = -5x^3 +17x^2 -6x#