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Multiply the brackets and then simplify (x-2)(2x^2-3x-2)

Can someone please show how they work this out? As I don't know where I'm going wrong?

x x 2x^2 = 2x^3 -2x 2x^2= -8x^2
x x 3x = 3x^2 -2 x -3x= 6x
x x -2 = -2x -2 x -2 = 4

2x^3
*middle bit should be 7x^2 * (but i keep getting -3x^2 + -8x^2 = -11x^2)
2x+6x= 4x
4

1 Answer

6 votes

Step-by-step explanation: when we have a binomial multiplied by a trinomial, we need to distribute all the terms in the binomial through all the terms on the trinomial.

So distributing the x through the parentheses, we get

2x^3 - 3x^2 -2x

Now we distribute the-2 through the parentheses.

so we get -4x^2 + 6x + 4.

Now combine to get 2x^3 - 7x^2 + 4x + 4.

User Anatoly Lubarsky
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