You must first transform into a multiplication and then factor to see what you can eliminate.
Explanation:
To transform a fractional division into a multiplication, you have to inverse the numerator and the denominator of the second fraction.
<span><span><span><span>x2</span>−4</span><span><span>x3</span>+7<span>x2</span></span></span>×<span><span><span>x2</span>+4x−21</span><span><span>x3</span>−<span>x2</span>−6x</span></span></span>
<span><span><span><span>(x+2)</span><span>(x−2)</span></span><span><span>x2</span><span>(x+7)</span></span></span>×<span><span><span>(x+7)</span><span>(x−3)</span></span><span>x<span>(x−3)</span><span>(x+2)</span></span></span></span>
Since <span><span>aa</span>=1,a=</span> all real numbers, we can proceed by eliminating factors that appear in the numerator and the denominator.
We are left with <span><span><span>x−2/</span><span>x^3</span></span></span>
