How do you verify whether rolle's theorem can be applied to the function f(x)=absxf(x)=|x| in [-1,1]?

1 Answer
Nov 22, 2016

According to Rolle's Theorem, there are three criteria for us to able to apply the theorem:

1.) f(x)f(x) must be continuous on [a,b][a,b]
2.) f(x)f(x) must be differentiable on (a,b)(a,b)
3.) f(a) = f(b)f(a)=f(b)

Explanation:

f(x) = |x| ->f(x)=|x| is not differentiable at x=0 which isin[-1, 1][1,1]

:. We cannot apply Rolle's Theorem