Express
$$\frac{4x}{x^2 - 9} - \frac{2}{x + 3}$$
as a single fraction in its simplest form. - Edexcel - A-Level Maths Pure - Question 3 - 2017 - Paper 4
Question 3
Express
$$\frac{4x}{x^2 - 9} - \frac{2}{x + 3}$$
as a single fraction in its simplest form.
Worked Solution & Example Answer:Express
$$\frac{4x}{x^2 - 9} - \frac{2}{x + 3}$$
as a single fraction in its simplest form. - Edexcel - A-Level Maths Pure - Question 3 - 2017 - Paper 4
Step 1
Combine the fractions
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Answer
To combine the fractions, find a common denominator. The expression can be rewritten as:
(x+3)(x−3)4x−(x+3)(x−3)2(x−3)
This gives:
(x+3)(x−3)4x−2(x−3)
Step 2
Simplify the numerator
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Answer
Now simplify the numerator:
4x−2(x−3)=4x−2x+6=2x+6
Thus, we can rewrite the expression as:
(x+3)(x−3)2x+6
Step 3
Further factor the numerator
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Answer
The numerator can be factored further:
2(x+3)
Substituting this back:
(x+3)(x−3)2(x+3)
Step 4
Cancel common factors
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