# Injective/Surjective question

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1. How do I prove that f(x) = x^1/2 + x is injective and surjective when the domain and range [0, +∞).

Cheers
2. (Original post by BobbleHats97)
How do I prove that f(x) = x^1/2 + x is injective and surjective when the domain and range [0, +∞).

Cheers
The function is continuous and increasing on that range and the limit is +infinity hence injective and surjective. I bet you are not happy with this are you ?

You prove by using the definition..
BTW- wrong forum section.
3. (Original post by hassassin04)
The function is continuous and increasing on that range and the limit is +infinity hence injective and surjective. I bet you are not happy with this are you ?

You prove by using the definition..
BTW- wrong forum section.
which forum section should i be in? Thanks
4. (Original post by BobbleHats97)
which forum section should i be in? Thanks
Maths Academic Help, this forum is for university courses.
And my answer is not very complete you know... One should be careful and state the results.. first of all for surjectivity that the range of the function is [0, +infty] and then its IVT that gives the result and such..

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