find the bound on the real zeros of the polynomial function

Question

f(x)=x^4+x^3-4x-6
cna you please show me how you got the answer please

Answer 1

you can use the synthetic division to find the smallest k such that (x-k) causes all the values in the bottom line to be positive.

Or, to provide an easier (but rougher) bound, see

http://www.mathsisfun.com/algebra/polynomials-bounds-zeros.html