- #1

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## Homework Statement

I'm actually a tutor, and a student has shown me one of their assignments. I think there's a notation error, I'm quite confident there is actually, but I don't want to assert this, or have my student go asserting it, without some more certainty.

This is the question

imgur link: http://i.imgur.com/A3ZEHi1.png

Now, shouldn't the inverse function be written [itex]f^{-1} (V)[/itex]?

I've written to the guy saying

"They've said solve for t in terms of V to find the inverse function...now, since there are only two variables, V and t, and inverting any relationship between them would just be finding one in terms of the other, f^{-1} is t as a function of V, so they should write it as f^{-1} (V)...right? I mean, you need to input V into the inverse function to find t...so therefore the inverse function is a function of V. So it should be written as f^{-1} (V). That's what I'd say anyway, I'm not a PhD in math, so I don't want to get over-confident about it.

It's not a big deal, and I'm sure the tutors and lecturers know perfectly well what they're doing, I'd say it would be a typo, but it could potentially lead to some confusion or misunderstanding in some instances...if I'm correct :)"

There has to be a domain change right? It makes no sense for the inverse to be in terms of t.