Quick inverse question...

DmanDmythDledge

"Use the functions f (x) = 1/8 (x) - 3 and g (x) = x^3 to find the indicated value.

(g inverse . f inverse) (-3) "

In the above line that should be a mini circle, don't know how to write the notation or remember what it's called but I can remember how to do the question.

Anyway my question is what should I do with the -3? Multiply what I get by minus 3 or fill it it to the equation for x or let the equation equal minus 3?

Yakuza

I would say the -3 is the parameter for the first function, so find f inverse of -3 and then g inverse of that. It's hard to tell without seeing the proper noatation.

Fremen

It's called "composition of functions". The circle is read as "after" so what you wrote is "g inverse after f inverse".

You know how to find g inverse and f inverse, right? What you're looking for is g inverse after f inverse, so if

x = (f inverse)(-3),
you want (g inverse)(x).

As a "sanity check" you should make sure that f of g of that number gives you -3 again.
(since f(g(g inverse(f inverse(x)))) = x).

MathsManiac

From the title of the thread, I was expected you to give us an answer and ask us to find the question!