SOLUTION: Write {{{"ln"}}}{{{sqrt(3/8)}}} as a sum or difference of rational multiples of natural logarithms of integers as small as possible.

I'm quite sure your teacher wanted you to do something other than just
approximate the value by punching a calculator as the other tutor assumed.
So I changed the instructions to what I think your teacher meant for you to
do.  When you post here always give the instructions, so we'll know what you
are required to do.

Change the square root to the  power:





Use the logarithm rule:  



Use the logarithm rule:   on the second factor, being sure to use brackets so that
the  in front will apply to the entire difference and not
just to the first term:



Write  as 



Use the logarithm rule:   again on the second term inside the brackets:




Remove the bracket by distributing:



Edwin