Finding X-intercept using Intermediate Value Theorem

[crazyphy]

Homework Statement

a.Prove that the function f(x)=x-(arctan x)^2+8arctan x -19 has one x- intercept.
b.Let Xo be the x-intercept of f(x). Use the intermediate value Theorem to find two consecutive integers n1,n2 such that n1 biger than Xo and Xo biger than n2

Homework Equations

The Attempt at a Solution

 

[malawi_glenn]

dude, no one will help you unless you show some work. What forumlas you know of and were you are stuck and so on.