Hi I need to find the values of x for which
Now I could - 4(x-3)/(x-3) from the RHS to the LHS, which is what the markscheme does, but why cant I do this:
that only gives me x = 0 and i as opposed to the other way which gives me 0,3,i
Why doesn't the stupid math work?
Thanks
Sorry I didn't make myself clear The method what you posted above is what works , but I understand why the method I posted earlier doesn't work either. I'm multiplying x-3 to the other side of the inequality but following it through makes me lose x=3 root. I don't see why
Thanks
Don't multiply through by . This could be a minus number, and you should know that if you multiply an inequality by a minus you need to swap the sign around.
The method to use is to either subtract like in the above example, or multiply through by as you know this is a positive number.