- #1
Janinever
- 13
- 0
Hi everybody!
I've hit a blank with regards to this 1 equation on a old exam paper - think I've overloaded myself a bit and just feel a bit like a airhead at the moment!
I understand the actual method and getting to the answer but it starts off with a equation which you then need to get to a standard form to use the formula to check if the roots are rational.
The initial equation is this :
4x^2 + 2kx - k = 2x
Then on the memorandum this is taken to standard form so the info can be substituted into the formula Δ = b^2 - 4ac
the standard form they then write that initial equation in is :
4x^2 + 2(k-1)x-k = 0
How do they get from 4x^2 + 2kx - k = 2x to this 4x^2 + 2(k-1)x-k = 0
The rest I understand entirely. Literally just the above has be scratching my head!
Please help :)
Thank you!
I've hit a blank with regards to this 1 equation on a old exam paper - think I've overloaded myself a bit and just feel a bit like a airhead at the moment!
I understand the actual method and getting to the answer but it starts off with a equation which you then need to get to a standard form to use the formula to check if the roots are rational.
The initial equation is this :
4x^2 + 2kx - k = 2x
Then on the memorandum this is taken to standard form so the info can be substituted into the formula Δ = b^2 - 4ac
the standard form they then write that initial equation in is :
4x^2 + 2(k-1)x-k = 0
How do they get from 4x^2 + 2kx - k = 2x to this 4x^2 + 2(k-1)x-k = 0
The rest I understand entirely. Literally just the above has be scratching my head!
Please help :)
Thank you!