SOLUTION: I would like help with the following: If f(x)=x(x+3)(x-1), use interval notation to give all values of x where f(x)is less than 0. Thank you.

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I would like help with the following: If f(x)=x(x+3)(x-1), use interval notation to give all values of x where f(x)is less than 0. Thank you.      Log On


   

Question 43893: I would like help with the following: If f(x)=x(x+3)(x-1), use interval notation to give all values of x where f(x)is less than 0. Thank you.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If f(x)=x(x+3)(x-1), use interval notation to give all values of x where f(x)is less than 0.
The zeroes are x=0,-3, and 1.
Plot these points on a number line.
Check values in each interval to determine if f(x)<0 in that interval.
For example choose a value between -3 and 0, say x=-1
f(-1)=-1(+2)(-2)>0 so the interval (-3,0) is not part of the solution.
Check also (-inf,-3), (0,1), (1,inf)
Cheers,
Stan H.