Determining if a function is injective

[markosheehan]

is the function x³-5x²+3x+5 injective. how can you tell

 

[Evgeny.Makarov]

Re: calculus

You can determine if the function has a local extremum. If a function is continuous and has, say, a maximum, then it is not injective since it assumes the same values on both sides of that point of maximum.