What does it mean for a function to be unique?

  • Context: High School 
  • Thread starter Thread starter FizX
  • Start date Start date
  • Tags Tags
    Function Mean
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
3 replies · 15K views
FizX
Messages
9
Reaction score
0
What does it mean for a function to be unique?
 
Physics news on Phys.org
In what context?

To say that y is a function of x if and onliy if for each choice of x there exist a UNIQUE y corresponding to that x.
This is part of the DEFINITION of a function in general.

Having a problem where we say that there exist a unique function as our solution (of for, example a differential equation) is the uniqueness property of our problem.
 
To say that a function, satisfying certain conditions is "unique" means that it is the only function satisfying those conditions.

For example, there is a unique function, y(x), satisfying y"= -y, y(0)= 0, y(1)= 1. (That unique function is y(x)= sin(x).)