The only way is to use the method of iteration. I made up the following code in R:

[php]d=1.5;x=1.5

while(d>.000001)

{

x.updated=100*log(x,base=10)

d=abs(x.updated-x)

x=x.updated

}

x.updated[/php]

[php]

d=1.5;x=1.5

while(d>.000001)

{

x.updated=10^(x/100)

d=abs(x.updated-x)

x=x.updated

}

x.updated[/php]

Run it in R; you will get the results.