![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
Factor the each monomial.
\r = r
\r4 = r · r · r · r
\The GCF is the product of the common prime factors in each monomial.
\The common prime factor is only r. So, the GCF is r.
\The greatest common factor of r and r4 is r.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The greatest common factor of r and r4 is r.