SOLUTION: what is the factored form of 4x^3-10x2-8x+6

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Question 985173: what is the factored form of 4x^3-10x2-8x+6
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

4x³-10x²-8x+6

Factor out 2

2(2x³-5x²-4x+3)

All the candidates for rational zeros are

±1, ±1/2, ±3, ±3/2 

We try 1 with synthetic division:

1 | 2  -5  -4   3
  |     2  -3  -7
    2  -3  -7  -4

That doesn't work because the last number on
the bottom is -4 not 0.

We try -1

-1 | 2  -5  -4   3
   |    -2   7  -3
     2  -7   3   0

So x+1 is a factor. so 

2(2x³-5x²-4x+3) becomes

2(x+1)(2x²-7x+3)

The quadratic factors and the complete factorization is:

2(x+1)(x-3)(2x-1)

Edwin