The function is
and
.
Rolle
s theorem :
Let
be a function that satisfies the following three hypotheses.
1.
is continuous on
.
2.
is differentiable on
.
3.
.
Then there is a number
in
such that
.
The function is
.
The function
is continuous on the interval
.
Substitute
in
.


.
Substitute
in
.


.

Rolle
s theorem is applicable.
The function
.
Differentiating on each side with respect to
.
Apply Quotient rule in derivatives
.




is differentiable on the open interval
, which satisfies the Rolle
s Theorem.


Solve the equation
.
Compare it to 

Roots are
.




is in the interval
.
The function
satisfy the rolle
s theorem.
.