Posted by Connor on .
7x^324x^219x+12
=f(x)
2x^34x^240x+80
Determine all values of x for which f is not defined.

Pre Calc 
Dave,
thats supposed to be a fraction all equel to f(x).

Pre Calc 
Reiny,
A function is not defined if the denominator is zero
So we just have to look at the bottom which I will assume is
2x^3  4x^2  40x + 80
by grouping
= 2x^2(x2)  40(x2)
= (x2)(2x^2  40)
so x2 cannot be zero, or x ≠ 2
or
2x^  40 ≠ 0
x^2 ≠ 20
x ≠ ±√20 or ±2√5
so x ≠ 2, 2√5, 2√5