How do I write the mathematical degree of a root

[lacuna]

What I’m trying to do

I don’t even know what I can try in this problem to solve it, I just write the degree of the root before the radical sign, but it doesn’t look the way I want it to. In screenshot 1 is a view of what it looks like, in screenshot 2 I showed how I would like it to look like

Things I have tried

As I said earlier, the solution to the problem remains the ridiculous writing of the degree of the root before the radical sign.

[holroy]

Try doing $ b = \sqrt[n]{a}$ as suggested here: How to write roots other than square roots in MathJax? - Mathematics Meta Stack Exchange