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Algebraic Fractions (GCSE)

Stuck on a question from a MathsWatch worksheet. I am aware this is a cubic but I have no idea what to do with it. MathsWatch says the answer is 2.75 but I don't know how to get there. Could someone be an angel and point me in the right direction? :colondollar:

Solve:

3x+2+1x−2=7x2−4\dfrac{3}{x+2} + \dfrac{1}{x-2} = \dfrac{7}{x^2-4}
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Original post by QPRTeags
Stuck on a question from a MathsWatch worksheet. I am aware this is a cubic but I have no idea what to do with it. MathsWatch says the answer is 2.75 but I don't know how to get there. Could someone be an angel and point me in the right direction? :colondollar:

Solve:

3x+2+1x−2=7x2−4\dfrac{3}{x+2} + \dfrac{1}{x-2} = \dfrac{7}{x^2-4}


Unless I'm missing something, you can simplify the RHS on line 3 =(7x2−4)(x−2)(x+2)=\left ( \dfrac{7}{x^2-4} \right ) (x-2)(x+2).
(edited 9 years ago)
Original post by QPRTeags
Stuck on a question from a MathsWatch worksheet. I am aware this is a cubic but I have no idea what to do with it. MathsWatch says the answer is 2.75 but I don't know how to get there. Could someone be an angel and point me in the right direction? :colondollar:

Solve:

3x+2+1x−2=7x2−4\dfrac{3}{x+2} + \dfrac{1}{x-2} = \dfrac{7}{x^2-4}

If you know how to add number fractions, then apply the same method to the left hand side of the question

3x+2+1x−2=3(x−2)+1(x+2)(x+2)(x−2))\frac{3}{x+2}+\frac{1}{x-2}=\frac{3(x-2)+1(x+2)}{(x+2)(x-2))}

Does that help?
Original post by QPRTeags
Stuck on a question from a MathsWatch worksheet. I am aware this is a cubic but I have no idea what to do with it. MathsWatch says the answer is 2.75 but I don't know how to get there. Could someone be an angel and point me in the right direction? :colondollar:

Solve:

3x+2+1x−2=7x2−4\dfrac{3}{x+2} + \dfrac{1}{x-2} = \dfrac{7}{x^2-4}

Sorry _ I hadn't seen your workings.

If you expand the denominator of the LHS you will see that it equals that of the RHS. So numerators must be equal too.

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