Question

C=√(m+√(m+√(m+⋯)) )

Answer 1

only that ??

Answer 2

Have a look at this page

http://en.wikipedia.org/wiki/Nested_radical

look at the section titled "Infinitely nested radicals"

Answer 3

As the terms add upto infinity, we can take the terms with one lesser 'm' also as C... so you get a quadratic equation in C,
C^2 = m + C... Now on solving this, you can get value of C in terms of 'm'...