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Simple P2 Algebra

Could anyone help;

Express as a single fraction in it's lowest terms.

1-x²/4x(7+x) x 6x²/3+x-2x²

Try using

3 + x - 2x^2 = (1 + x)(3 - 2x),
(1 - x^2) = (1 - x)(1 + x).

If you get stuck, scroll down:

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[(1 - x^2)/4x(7 + x)] * [6x^2/(3 + x - 2x^2)]
= 6x^2 (1 - x^2) / 4x(7 + x)(3 + x - 2x^2)
= 6x^2 (1 - x)(1 + x) / 4x(7 + x)(1 + x)(3 - 2x)
= 3x(1 - x) / 2(7 + x)(3 - 2x)

Thanks for that.

Ah, my minds gone blank! :frown:

How do you factorise:

12x² - 42x + 18

And,

4x² - 36

Reply 4

Hoofbeat

BurnOut

Ah, my minds gone blank! :frown:

How do you factorise:

12x² - 42x + 18

And,

4x² - 36

for the first one:
take a 6 out first -> 6(2x^2 -42x + 18)
to get values of x, i think you have to use the quadratic formula

for the 2nd one:
this is a difference of 2squares, therefore 4x^2 -36 = (2x-6)(2x+6)