Question

find a bound on the real zeros of the polynomial functions.

f(x)=x^4+7x^3-x-2

every real zero of f lies between - ? and ?

Answer 1

x^4+7x^3-x-2 = 0
no simple way to solve this, so ....
Wolfram says:
http://www.wolframalpha.com/input/?i=x%5E4%2B7x%5E3-x-2+%3D+0

real roots are -6.99 and .705

There are only those two real roots, so there are no other real roots between ....