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Someone help factorise this [Solved] watch

1. Um, I'm a bit rusty with my factorisation skills but can someone show me how I should factorise this please?

7u² - 8u + 1 = 0
2. You coulde use the Quadratic formula or
Put the 7u and u in brackets find something that times together to make 1 so that would be 1X1, then put in the signs
(7u-1)(u-1)
3. (Original post by sunny_veggies)
You coulde use the Quadratic formula or
Put the 7u and u in brackets find something that times together to make 1 so that would be 1X1, then put in the signs
(7u-1)(u-1)
Wrong, that is used to solve the equation not to factorise.
True
4. Find two numbers that have multiply to make 7 and add to make -8, which are -7, -1, so you get

7u² - 7u-1u + 1 = 0

then factorise 7u^2 - 7u, and -1u + 1, then you should know what to do if you are being truthful about ur A* in maths
5. (Original post by jit987)
Wrong, that is used to solve the equation not to factorise.
True
Ahhh I see what I did wrong...

The actual question I was doing was solving the equation of:

7^2x+1 - 8 x 7^x + 1 = 0 where u = 7^x

and i got to 7u² - 8u + 1 = 0, and when I factorised I got 1, and 1/7

I was doing the question out of the book, and checked for answers at the back, and saw 0, and -1, and was thinking I factorised wrong, but it was just me forgetting the last bit of:

7^x = 1, x = 0

7^x = 1/7
x = -1

Anyway thanks guys
6. (Original post by jit987)
Wrong, that is used to solve the equation not to factorise.
True
No its not, you can work back from those answers and put them into brackets, i wouldnt personally do it that way but you can
7. (Original post by Extricated)
Find two numbers that have multiply to make 7 and add to make -8, which are -7, -1, so you get

7u² - 7u-1u + 1 = 0

then factorise 7u^2 - 7u, and -1u + 1, then you should know what to do if you are being truthful about ur A* in maths
Yes I did get an A* in Maths GCSE lol xD, and look at my above post
8. (Original post by EternalDoom)
Yes I did get an A* in Maths GCSE lol xD, and look at my above post
LOL anytime

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