Posted by Deb on .
Find the bounds on the real zeros of the following function. Please show all of your work.f(x)=x^4+2x^3x^21

Precalculus 
Reiny,
Make a rough sketch.
A few buttonpushes on your calculator will show that there is a zero near 2.5 and another between 1/2 and 1
for x's > 1 and x < 2/5 the function just "blows up"
looks like 2 reals and 2 complex roots