##### Algebra 2 test needs all work shown

 Algebra Tutor: None Selected Time limit: 1 Day

if f(x)=x to the third power -ax 8 and f to the negative 1 power(52)=4 find the value of a

Mar 21st, 2015

So with the caveat that it's not clear what "-ax 8" is... presumably there should be an operator between the x and the 8?

The key is to understand what f^-1(x) is, the inverse function of x. It's very simple - if f(x) = some expression involving x, then given a value for x, you can find f(x). f^-1(x) just works in reverse (being the inverse function). If you know the value for f(x), and plug it in to the f^-1(x) inverse function, it will spit out the original value of x.

So, you don't actually need to know what f^-1(x) is. You're told that f^-1(52) = 4. That means that for f(x)=52, you have x = 4.

So just substitute these into your original equation for f(x). I'm going to assume the missing operator is a +, but it will be easy for you to adjust this if it's something else:

f(x) = x^3 - ax + 8

52 = (4)^3 - 4a + 8

52 = 64 - 4a + 8

4a = 20

a = 5

Mar 21st, 2015

It was very helpful! Is there any chance you can help me with this one too?

[f of g of p](x)

where:
f(x)=3x^2-13x-10
g(x)=7(x+2)^2
p(x)=-x-2​

Mar 23rd, 2015

Glad I could help, but you should post additional questions separately on the site (this space is for follow-ups specifically related to the original task).

Mar 23rd, 2015

I keep trying, on multiple accounts, but it's not letting me ask any more questions. There's a glitch on the site

Mar 23rd, 2015

I can certainly see new questions being posted, so I don't think it's a glitch with the site as a whole - perhaps it's something to do with having multiple accounts? I am pretty certain that is against the rules and spirit of a site like this where reputation and history are important (for example, I will simply not take on large amounts of work from users with zero history, hidden identities or a history of failing to pay after work was completed, it isn't worth the hassle!).

Mar 23rd, 2015

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Mar 21st, 2015
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Mar 21st, 2015
Dec 4th, 2016
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