Answer:
x^3 +2x^2 -4x -8
Explanation:
The factors of x^2 +4x +4 are (x +2)^2.
The factors of 4 -x^2 are -1(x -2)(x +2).
The least common denominator is the least common multiple of these, excluding the -1 multiplier. That multiple is ...
... (x +2)^2 × (x -2) = x^3 +2x^2 -4x -8
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Comment on the minus sign
When the given fractions are expressed using the denominator above, the second one will need to have its numerator sign adjusted. The two fractions are ...
- 7(x -2)/(x^3 +2x^2 -4x -8)
- -5(x +2)/(x^3 +2x^2 -4x -8)