# one to one function

• Oct 6th 2012, 07:41 AM
ubhutto
one to one function
i dont understand how to prove it

if f is a one-to-one fuction, prove that g(x) = -f(x) is also one-to-one

can you show the steps

thanks alot
• Oct 6th 2012, 07:53 AM
Plato
Re: one to one function
Quote:

Originally Posted by ubhutto
i dont understand how to prove it
if f is a one-to-one fuction, prove that g(x) = -f(x) is also one-to-one
can you show the steps

The function $\displaystyle f$ is one-to-one if and only if $\displaystyle f(x) = f(y) \Rightarrow \;x = y\text{ or }x\ne y \Rightarrow \;f(x) \ne f(y)$

No I will not do this problem for you. That is yours to do.
Just apply the above to $\displaystyle g(x)~.$
• Oct 6th 2012, 08:55 AM
ubhutto
Re: one to one function
lol i did not ask you to do the problem for me i asked you to explain it to me
• Oct 6th 2012, 09:10 AM
Plato
Re: one to one function
Quote:

Originally Posted by ubhutto
lol i did not ask you to do the problem for me i asked you to explain it to me

What do you think "can you show the steps" means if not 'do it for me'?

Show that if $\displaystyle g(x)=g(y)$ then $\displaystyle x=y$.
• Oct 6th 2012, 05:43 PM
ubhutto
Re: one to one function
"can you show the steps" means that i am trying to understand how to do it for future tests and stop being ignorant, if you don't want to help properly then don't.
• Oct 6th 2012, 05:44 PM
ubhutto
Re: one to one function
and thanks 'alot' for your help, next time please don't help me because apparently you cannot explain properly