echo(mPow(7,9)); - Echos 7 to the power of nine.
echo(mSqrt(4,2)); - Echos the square root of 4.
echo(mSqrt(27,3)); - Echos the cubed root of 27.
Test things before you post them
mSqrt() is strictly for square-roots
And it will return an error for having an extra argument