If f(x) = 3x^2+ 3x^(1/2) + 3x, then f(-9) is equal to
Accepted Solution
A:
Since[tex]f(x)=3x^2+3\sqrt{x}+3x[/tex]the domain of f(x) is the set of non-negative integers, because we can't feed a square root with negative inputs. So, you couldn't comput f(-9)Unless you're allowed to use complex numbers, in that case we have[tex]f(-9)=3\cdot (-9)^2+3\sqrt{-9}+3\cdot (-9)=3\cdot 81+3\cdot (9i)-27[/tex]Which evaluates to[tex]243+27i-27=216+9i[/tex]