Apply the property of negative integer exponents to rewrite 15^38 as an expression with positive exponents only
The property of negative integer exponents states that for any non-zero number x and negative integer n,
x^n = 1/(x^(-n))
Applying this property to 15^38, we can rewrite it as:
15^38 = 1/(15^(-38))
Therefore, the expression with positive exponents only is 1/(15^(-38)).