Hello, I've come across a problem in my textbook that really baffles me.
Task: to use substitution to solve the equation for x:
It was easy to make the quadratic equation,
but solving for x was a bit "ugly" (quoted because math is NOT ugly )
I've spent quite a time over this, any pointers?
Thanks for the reply CaptainBlack.
That's exactly what I did, but I ended up with a complex solution (i.e. "wrong") for and square roots of square roots of whatever (rightfully wrong) for . Could you be a bit more verbose?
P.S.
The solution is supposed to be
First off: There are four solutions to this equation. Two complex and two real. You have listed only the two real solutions.
Second: Your quadratic in u is incorrect.
so
So we wish to have
So
a = 1
b = 3
c = -4
Thus
So u = -4 or u = 1.
Thus
==>
and
==>
-Dan
(Rats! FOILed again. )