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# kjyugjhvl watch

1. jgfjgjghh
2. (3x-1)(3x-1)(3x-1)=[(3x-1)(3x-1)](3x-1)

simply ignore the final bracket until you've worked out the ones in the [] brackets, then using the same method mulitply out what you get from [] with the (3x-1) on the end

EDIT: fatchicksftw.
3. 9x^2 -6x + 1
4. Binomial expansion??
5. a)Try doing just simply (3x-1)(3x-1) and what do you get?

6. sorry, did i just MERK YOU ALL!

muhahahaha.
7. steve2005 laid out the way i would explain doing it OP
8. If you know binomial expansion, then it's just
9. (Original post by steve2005)
I can get the 9x^2 and the +1 but I cannot work out how you get the 6x when you merge out the two brackets.
10. Expanding the second two brackets is just like expanding a quadratic function ; then you just multiply through again.

Say you have something with 5 brackets (...)(...)(...)(...)(...), then you can tackle it by multiplying everything in the 4th bracket with everything in the 5th, and then everything in the 3rd with what you just worked out for the 4th and 5th, then everything in the 2nd with everything that you just worked out for the 3rd, 4th and 5th, and so on... for example:

Simples *squeak*

But really, expanding brackets is quite basic GCSE stuff... what level are you working at here?
11. (Original post by ilovefatchicks)
I can get the 9x^2 and the +1 but I cannot work out how you get the 6x when you merge out the two brackets.

12. OMG a maths question on tsr i can actually do!!!

So,

(3x-1)(3x-1)(3x-1)
= (3x-1)(9x^2 -3x - 3x +1)
= 27x^3 - 9x^2 -9x^2 + 3x
-9x^2 +3x +3x -1
= 27x^3 - 27x^2 + 9x -1

(probably beaten to it but heyho..)

EDIT: why does it say -2 at the end?!? Sorry if i'm wrong!!
13. (Original post by ilovefatchicks)
I can get the 9x^2 and the +1 but I cannot work out how you get the 6x when you merge out the two brackets.
Thats because you multiply 3x by -1 to get -3x, and then again. You then add the answers together like so: -3x + -3x = -6x

Remember to do that as well as 3x*3x and -1*-1.
14. (3x-1) * (3x-1)

FOIL
First = 3x * 3x = 9x^2
Outside = -1*-1 = +1
inside = -1 * 3x = -3x
Last = -1 * 3x = -3x
collect terms

9x^2-6x+1
15. (Original post by nuodai)
Expanding the second two brackets is just like expanding a quadratic function ; then you just multiply through again.

Say you have something with 5 brackets (...)(...)(...)(...)(...), then you can tackle it by multiplying everything in the 4th bracket with everything in the 5th, and then everything in the 3rd with what you just worked out for the 4th and 5th, then everything in the 2nd with everything that you just worked out for the 3rd, 4th and 5th, and so on... for example:

Simples *squeak*
Compare the meerkat dot com, compare the market dot com.
16. (Original post by ilovefatchicks)
I can get the 9x^2 and the +1 but I cannot work out how you get the 6x when you merge out the two brackets.

etc
17. (Original post by PGtips92)
EDIT: why does it say -2 at the end?!? Sorry if i'm wrong!!
You're correct, it's -1.
18. e=mc2
19. (Original post by Arctic_wombaT)
e=mc2
Wow, I'm completely taken aback by your wit... you should consider a career in stand-up comedy

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