SOLUTION: Find the domain and range and sketch the graph for the functions f and g where f(x) is given by the polynomial below and g(x)=|f(x)|. Also use the graph to solve the inequality f(x

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find the domain and range and sketch the graph for the functions f and g where f(x) is given by the polynomial below and g(x)=|f(x)|. Also use the graph to solve the inequality f(x      Log On


   



Question 992558: Find the domain and range and sketch the graph for the functions f and g where f(x) is given by the polynomial below and g(x)=|f(x)|. Also use the graph to solve the inequality f(x)<0.
f(x)=9+3x-2x^2

Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
Find the domain and range and sketch the graph for the functions f and g where f(x) is given by the polynomial below and g(x)=|f(x)|.
Also use the graph to solve the inequality f(x)<0.
f(x)=9+3x-2x^2
----------------------------------------------------------------------------

The domain of the function  f  is the entire number line,  i.e.  the set of all real numbers.  (It is so for any polynomial).

The domain of the function  g  is the same entire number line,  i.e. the set of all real numbers.
The plots of  f  and  g  are shown in the Figure below.  The plot of  g  is in green.  Partly it is over-posed the plot of  f.



The roots of f are  3  and  -3%2F2.
f(x) < 0  in two semi-infinite intervals  (-infinity, -3%2F2)  and  (3, infinity).