CHECK Multiply the divisor, by the quotient, The product must be
the original dividend,
✓
Divisor Quotient
Dividend NOW TRY
Dividing a Polynomial by a Polynomial
Divide.
The first polynomial must be written in descending powers as
Then divide by
- 6 Remainder
4 x- 2
4 x- 8
- 2 x^2 + x
- 2 x^2 + 5 x
4 x^3 - 2 x^2
2 x- 1 4 x^3 - 4 x^2 + 5 x- 8
2 x^2 - x+ 2
2 x- 1.
4 x^3 - 4 x^2 + 5 x- 8.
5 x+ 4 x^3 - 8 - 4 x^2
2 x- 1
EXAMPLE 6
= 3 x^2 - 5 x- 28
1 x- 4213 x+ 72 = 3 x^2 + 7 x- 12 x- 28
3 x^2 - 5 x-28.
x-4, 3 x+7.
Each time you
subtract, add
the opposite.
Write in
descending
powers.
Step 1 divided by.
Step 2 Subtract. Bring down the next term.
Step 3 divided by.
Step 4 Subtract. Bring down the next term.
Step 5 4 xdivided by is.
Step 6 Subtract. The remainder is. Write the remainder as the numerator of a
fraction that has as its denominator. Because of the nonzero
remainder, the answer is not a polynomial.
4 x^3 - 4 x^2 + 5 x- 8
2 x- 1
= 2 x^2 - x+ 2 +
- 6
2 x- 1
2 x- 1
- 6
2 x 2 212 x- 12 = 4 x- 2
- 2 x^22 x is -x -x 12 x- 12 =- 2 x^2 +x
4 x^32 x is 2 x^22 x^212 x- 12 = 4 x^3 - 2 x^2
Dividend
Divisor
Quotient
polynomial Fractional part
of quotient
Remainder
Divisor
344 CHAPTER 5 Exponents and Polynomials
Remember to add.
Don’t forget the sign.+
remainder
divisor
Dividing a Polynomial by a Polynomial
Divide.
Step 1 divided by xis 3x.
3 x 1 x- 42 = 3 x^2 - 12 x
3 x^2
3 x^2 - 5 x- 28
x- 4
EXAMPLE 5
Step 2 Subtract from
Bring down
Step 3 7 xdivided by xis 7.
Step 4 Subtract 7 x- 28 from 7 x- 28.The remainder is 0.
71 x- 42 = 7 x- 28
3 x^2 - 5 x. -28.
3 x^2 - 12 x
NOW TRY
EXERCISE 5
Divide.
4 x^2 +x- 18
x- 2
NOW TRY ANSWER
- 4 x+ 9
Quotient
Dividend
Divisor
0
7 x- 28
7 x- 28
3 x^2 - 12 x
x- 4 3 x^2 - 5 x- 28
3 x+ 7
http://www.ebook777.com
http://www.ebook777.com