Checking a log answer

why is the second box not being evaluated like the first and third box?
I am evaluating the problem and answers at M=3 and N=4

Here is the slide. Thanks for any help!

If you type input2 into the regular desmos graphing calculator (with M and N defined), you get a warning to put the argument for log in parentheses, so it’s not valid there either. Just a syntax error for desmos. Same thing happens with trig functions.

Why would box 1 work on the slide?

And what is special about the root symbol, that they are requiring parentheses?
On the graphing calculator, this is allowed.
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