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#5
x3 - 7x-6 divide x + 2

#5 x3 - 7x-6 divide x + 2-example-1
User Abadis
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1 Answer

6 votes

Answer:

the quotient is 1x^2 - 2x - 3

Explanation:

Here we're dividing the polynomial x3 - 7x-6 by the binomial x + 2.

Synthetic division works very well here. To use synthetic division we must write out all four (not three) terms of x^3 - 7x - 6:

Divide x^3 - 7x - 6 by x + 2 => Divide x^3 + 0x^2 - 7x - 6 by x + 2.

Dividing by x + 2 is equivalent to using -2 as the divisor in synthetic division.

Write out the synthetic division layout:

-2 / 1 0 -7 -6

-2 4 +6

----------------------------------------

1 -2 -3 0

Because the remainder is zero (0), we know that x + 3 divides into x^3 + 0x^2 - 7x - 6 evenly. From the coefficients 1, -2 and -3, we know that the quotient is 1x^2 - 2x - 3.

Thus, x^3 + 0x^2 - 7x - 6 = (x + 2)(x^2 - 2x - 3)

User Stuartmclark
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