Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
oops made the same mistake as po-shen loh so i learned that \(\phi(mn)=\phi(m)\cdot\phi(n)\) and i applied the fact on this problem and i got 4 is the phi function only multiplicative (as in the above equation) when \(\gcd(m,n)=1?\)