The number is
.
Consider
.
.
Newtons approximation formula :
.
Consider
.
Apply derivative on each side with respect to
.

.
From the newtons method,
.
We have
and
is close to the
.
So consider
.
Substitutte
in
.

Substitutte
in above expression.

Repeat the process to get the value of the root, correct to eight decimal places are same.
\Consider
.
Substitutte
in above expression.
.
Substitutte
in above expression.




Hence
.
Approximation of the number
is
.
Approximation of the number
is
.