Inverse and Composite Inverse Functions

AI Thread Summary
The discussion focuses on a student's request for feedback on their homework related to inverse and composite inverse functions. They express uncertainty about their solutions, particularly for part c, and seek clarification on any special rules. Respondents provide constructive feedback, highlighting the importance of not leaving negatives in the denominator and introducing the rule for composite inverses. The student acknowledges the tips and expresses gratitude for the guidance received. Overall, the interaction emphasizes the collaborative nature of learning complex mathematical concepts.
Matty R
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Hello :smile:

I was wondering if someone could check my working and answers to these three homework questions. I've done the inverse functions in class, but not the composite inverse functions, if that's what they're called.

Homework Statement


http://img24.imageshack.us/img24/6035/question4t.jpg


Homework Equations


http://img25.imageshack.us/img25/2204/equations4.jpg


The Attempt at a Solution


http://img27.imageshack.us/img27/3402/attempt4a.jpg http://img27.imageshack.us/img27/9500/attempt4b.jpg


I'd appreciate any feedback. Parts a and b are just like I've done in class. Where I've left them is where we ended them in class. Part c is just a guess. I don't know if there is a special rule or something like that.

Thanks. :smile:
 
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It looks fine to me. Just a few tips, (x-2)/(-3)=(2-x)/3 , you generally don't want to leave negatives hanging at the bottom of fractions, and also f^{-1}h^{-1}=(hf)^{-1} may help you in the future.
 
Focus said:
It looks fine to me. Just a few tips, (x-2)/(-3)=(2-x)/3 , you generally don't want to leave negatives hanging at the bottom of fractions, and also f^{-1}h^{-1}= (hf)^{-1} may help you in the future.

Thanks for the reply. :smile:

I didn't know about not leaving negatives at the bottom of fractions. I'll make sure I don't do that in future. :smile:

I didn't know about the (hf)^{-1} bit either. I'm certain that will come up later in the course.

I really appreciate this. You've put my mind at ease. :smile:

Thanks again.
 
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