Like what you saw?
Create FREE Account and:
 Watch all FREE content in 21 subjects(388 videos for 23 hours)
 FREE advice on how to get better grades at school from an expert
 Attend and watch FREE live webinar on useful topics
Proving Two Functions are Inverses  Concept
Carl Horowitz
Carl Horowitz
University of Michigan
Runs his own tutoring company
Carl taught upperlevel math in several schools and currently runs his own tutoring company. He bets that no one can beat his love for intensive outdoor activities!
The definition of a function can be extended to define the definition of an inverse, or an invertible function. It's important to understand proving inverse functions, and the method of proving inverse functions helps students to better understand how to find inverse functions. Students should review how to find an inverse algebraically and the basics of proofs.
Proving two functions are inverses Algebraically. So when we have 2 functions, if we ever want to prove that they're actually inverses of each other, what we do is we take the composition of the two of them. So remember when we plug one function into the other, and we get at x. The key to this is we get at x no matter what the order is. So if we take f of g of x, claiming that f and g are inverses, we should get x. And also if we take g of f of x we should also get x, okay?
There is a chance that this could come out, and one of them could come out to be x, that doesn't prove that we have inverses on our hand. We realy need to do both, if they both come out to be x's. Voila! We have 2 inverses.
Please enter your name.
Are you sure you want to delete this comment?
Carl Horowitz
B.S. in Mathematics University of Michigan
He knows how to make difficult math concepts easy for everyone to understand. He speaks at a steady pace and his stepbystep explanations are easy to follow.
i love you you are the best, ive spent 3 hours trying to understand probability and this is making sense now finally”
BRIGHTSTORM IS A REVOLUTION !!!”
because of you i ve got a 100/100 in my test thanks”
Get Peer Support on User Forum
Peer helping is a great way to learn. Join your peers to ask & answer questions and share ideas.
Concept (1)
Sample Problems (4)
Need help with a problem?
Watch expert teachers solve similar problems.

Proving Two Functions are Inverses
Problem 1 5,424 viewsProve f(x) = 6x − 3 and g(x) = ⅙(x + 3) are inverses.

Proving Two Functions are Inverses
Problem 2 3,647 viewsProve f(x) = 2(x + 3) and f⁻¹(x) = ½x + 3 are inverses.

Proving Two Functions are Inverses
Problem 3 685 views 
Proving Two Functions are Inverses
Problem 4 715 views
Comments (0)
Please Sign in or Sign up to add your comment.
·
Delete