F(x) = 3x^2 + 9x + 12,
The zeroes of the function are the value of x when F(x)=0.
3x²+ 9x + 12 = 0 (divide all equation by 3)
x²+3x+4 =0
a=1, b=3, c=4
[tex]D= b^{2}-4ac=3^{2} -4*1*4=9-16= -4 \ \textless \ 0, so
no real solutions.
[/tex]
There are no real zeros for this function.