Asked by Lindsay
Determine if Rolle's Theorem can be applied. If it can, find all values of c such that f'(c)=0.
f(x)=x^3-9x, [-3,3]
f(x)=x^3-9x, [-3,3]
Answers
Answered by
Graham
f(x) is continuous over the domain. [-3,3]
f(x) is differential.
f'(x) = 3x<sup>2</sup> -9
f(x) has two equal value points on the independent axis.
f(-3) = f(3) = 0
Therefore Rolle's Theorem Applies
.: Exists c such that f'(c)=0
Solve for c:
0 = 3c<sup>2</sup> - 9
...
f(x) is differential.
f'(x) = 3x<sup>2</sup> -9
f(x) has two equal value points on the independent axis.
f(-3) = f(3) = 0
Therefore Rolle's Theorem Applies
.: Exists c such that f'(c)=0
Solve for c:
0 = 3c<sup>2</sup> - 9
...
Answered by
Me
Ahh! That's the answer I had but I was doubting it because my partner got something else! Thanks!