Question

Difficulty: MediumEquivalent Algebraic Expressions

Which of the following is equivalent to the expression 3x25x4x2\frac{3x^2 - 5x - 4}{x - 2} for all x2x \neq 2?

  1. A
    3x16x23x - 1 - \frac{6}{x - 2}
  2. 3x+12x23x + 1 - \frac{2}{x - 2}Answer
  3. C
    3x+1+2x23x + 1 + \frac{2}{x - 2}
  4. D
    3x54x23x - 5 - \frac{4}{x - 2}

Answer

3x+12x23x + 1 - \frac{2}{x - 2}
The correct answer represents the equivalent expression obtained by performing polynomial division on the rational expression. Dividing the numerator 3x25x43x^2 - 5x - 4 by the denominator x2x - 2 yields a quotient of 3x+13x + 1 and a remainder of 2-2. This can be written in the form of the quotient plus the remainder over the divisor, resulting in 3x+12x23x + 1 - \frac{2}{x - 2}.

Step-by-Step Solution

1
Divide the leading term of the numerator, 3x23x^2, by the leading term of the denominator, xx.
The first term of the quotient is 3x3x.
This starts the polynomial long division process.
2
Multiply 3x3x by the divisor (x2)(x - 2) and subtract the result from the numerator.
(3x25x4)(3x26x)=x4(3x^2 - 5x - 4) - (3x^2 - 6x) = x - 4.
Subtracting the multiplied term helps find the remainder of the first division step.
3
Divide the leading term of the remaining expression, xx, by the leading term of the divisor, xx.
The second term of the quotient is 11.
To continue the division process with the remaining terms.
4
Multiply 11 by the divisor (x2)(x - 2) and subtract the result from x4x - 4.
(x4)(x2)=2(x - 4) - (x - 2) = -2.
This step determines the final remainder of 2-2 because the degree of the remainder is now less than the degree of the divisor.
5
Express the final result as the sum of the quotient and the remainder divided by the divisor.
3x+12x23x + 1 - \frac{2}{x - 2}
To construct the equivalent algebraic expression.

Key Concept

Equivalent Algebraic Expressions
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