expand the expression log square root of x
``First we will rewrite the radical number using rational exponent.
`==gt sqrtx = x^(1/2) `
`==gt log sqrtx = log x^(1/2)`
Now we will use logarithm properties to simplify.
We know that `log a^b = b *log a`
```==gt log sqrtx = log x^(1/2) = (1/2) log x`