AQA AS Maths C1, C2 and S1B

Hi, guys we could use this thread for revision help and help us put a mark scheme together tomorrow. Feel free to link any questions.

(edited 8 years ago)

Reply 1

-jordan-

5

Just gonna do 3 past papers tonight. Core 1 is delightful if you go ahead and learn your stuff.

Reply 2

Charliejb

Has anyone got any quick ways of factorising quadratics where a doesn't = 1 (e.g. 6x^2 - 2x - 8)? It always takes me ages to find the right numbers.

Reply 3

lizard54142

6

Original post by Charliejb

Has anyone got any quick ways of factorising quadratics where a doesn't = 1 (e.g. 6x^2 - 2x - 8)? It always takes me ages to find the right numbers.

Yes! Would you like a photo of my technique?

Reply 4

-jordan-

5

Original post by Charliejb

Has anyone got any quick ways of factorising quadratics where a doesn't = 1 (e.g. 6x^2 - 2x - 8)? It always takes me ages to find the right numbers.

I just use the quadratic formula to find one solution and then factorise for the second. For the one you mentioned if it's equal to zero you can half it for the same solutions. 3x^2 -x - 4 becomes much easier to solve because the first bracket must contain 3x and the second x.

(edited 8 years ago)

Reply 5

Charliejb

Original post by lizard54142

Yes! Would you like a photo of my technique?

That would be very helpful, thanks

Reply 6

Charliejb

Original post by -jordan-

I just use the quadratic formula to find one solution and then factorise for the second. For the one you mentioned if it's equal to zero you can half it for the same solutions. 3x^2 -x - 4 becomes much easier to solve because the first bracket must contain 3x and the second x.

Thanks, I never thought of halving it first.

Reply 7

lizard54142

6

Original post by Charliejb

That would be very helpful, thanks

Note I have broken it down into every step here to help people understand, I usually do this in a couple seconds in my head (perhaps writingout the square to the side if it's more complex)!

Reply 8

Charliejb

Original post by lizard54142

Note I have broken it down into every step here to help people understand, I usually do this in a couple seconds in my head (perhaps writingout the square to the side if it's more complex)!