(x) - (x^2)/(x - 2) + (9)/(x^2 - 4) May someone help me combine these 3 fractions, because it says my answer is wrong.?
回答 (6)
2017-03-14 11:15 pm
x - [x²/ (x - 2)] + [9 / (x² - 4)]
= [x(x + 2)(x - 2) / (x + 2)(x - 2)] - [x²(x + 2) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [x(x² - 4) / (x + 2)(x - 2)] - [(x³ + 2x²) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [(x³ - 4x) / (x + 2)(x - 2)] - [(x³ + 2x²) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [(x³ - 4x) - (x³ + 2x²) + 9] / (x + 2)(x - 2)
= [x³ - 4x - x³ - 2x² + 9] / (x + 2)(x - 2)
= [-2x² - 4x + 9] / (x + 2)(x - 2)
= -(2x² + 4x - 9) / (x + 2)(x - 2)
The answer can also be written as: -(2x² + 4x - 9) / (x² - 4)
= [x(x + 2)(x - 2) / (x + 2)(x - 2)] - [x²(x + 2) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [x(x² - 4) / (x + 2)(x - 2)] - [(x³ + 2x²) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [(x³ - 4x) / (x + 2)(x - 2)] - [(x³ + 2x²) / (x + 2)(x - 2)] + [9 / (x + 2)(x - 2)]
= [(x³ - 4x) - (x³ + 2x²) + 9] / (x + 2)(x - 2)
= [x³ - 4x - x³ - 2x² + 9] / (x + 2)(x - 2)
= [-2x² - 4x + 9] / (x + 2)(x - 2)
= -(2x² + 4x - 9) / (x + 2)(x - 2)
The answer can also be written as: -(2x² + 4x - 9) / (x² - 4)
2017-03-14 11:51 pm
x (x - 2) (x + 2) - (x²) (x + 2) + 9
-----------------------------------------------
(x - 2) (x +2)
x (x² - 4) - x³ - 2x² + 9
---------------------------------
(x - 2) (x +2)
9 - 4x - 2x²
-------------------
(x - 2) (x +2)
-----------------------------------------------
(x - 2) (x +2)
x (x² - 4) - x³ - 2x² + 9
---------------------------------
(x - 2) (x +2)
9 - 4x - 2x²
-------------------
(x - 2) (x +2)
2017-03-14 11:11 pm
(x) - (x^2)/(x - 2) + (9)/(x^2 - 4)
= [x(x - 2) - x^2]/(x - 2) + 9/(x^2 - 4)
= [ x^2 - 2x - x^2]/(x - 2) + 9/(x^2 - 4)
= - 2x/(x + 2) + 9/(x^2 - 4)
= (- 2x^2 - 4x + 9)/(x^2 - 4)
= ( 9 - 4x - 2x^2)/(x^2 - 4)
= [x(x - 2) - x^2]/(x - 2) + 9/(x^2 - 4)
= [ x^2 - 2x - x^2]/(x - 2) + 9/(x^2 - 4)
= - 2x/(x + 2) + 9/(x^2 - 4)
= (- 2x^2 - 4x + 9)/(x^2 - 4)
= ( 9 - 4x - 2x^2)/(x^2 - 4)
2017-03-15 12:04 am
First give the three terms a common denominator.
The least common denominator is x²-4.
The least common denominator is x²-4.
2017-03-19 5:36 pm
(x) = (x²)/(x - 2) + 9/x² - 4
X(x² - 4) - x²(x + 2) + 9/(x² - 4)
X³ - 4x - x³ - 2x² + 9/(x² - 4)
- 2x² - 4x + 9/(x2 - 4)
X(x² - 4) - x²(x + 2) + 9/(x² - 4)
X³ - 4x - x³ - 2x² + 9/(x² - 4)
- 2x² - 4x + 9/(x2 - 4)
2017-03-14 11:22 pm
[(x) - (x^2)] / [(x - 2) + (9)] / [(x^2 - 4)]
= [x(1 - x) / (x - 2) + (9) / [(x^2 - 4)]
= [x(1 - x)(x + 2) + 9] / [(x^2 - 4)]
Quotient and remainder:
-x^3 - x^2 + 2 x + 9 = (-x - 1) × (x^2 - 4) + 5 - 2 x
= [x(1 - x) / (x - 2) + (9) / [(x^2 - 4)]
= [x(1 - x)(x + 2) + 9] / [(x^2 - 4)]
Quotient and remainder:
-x^3 - x^2 + 2 x + 9 = (-x - 1) × (x^2 - 4) + 5 - 2 x
收錄日期: 2021-04-18 16:07:45
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