1. ## Two quick questions.

Right now were having a functions test soon, and i need quick help fast please

One Q is :

Explain, without graphing, why 2x^2 -1=y^2 is not a function, explain specifically what rule it breaks.

2Q:
Determine algebraically if the funciton is even,odd or neither. Justidy your answer.

f(x)=2x^2 +1

( i know we have to do the f(-x) and -f(-x) stuff, but i dont understand how to do it)

2. Originally Posted by clearlyjunk

One Q is :

Explain, without graphing, why 2x^2 -1=y^2 is not a function, explain specifically what rule it breaks.

every x-value can only be mapped to one y-value

2Q:
Determine algebraically if the funciton is even,odd or neither. Justidy your answer.

f(x)=2x^2 +1

f(-x) = ?
...

3. now i need only help on the second one.

4. Originally Posted by clearlyjunk
now i need only help on the second one.
You have been given help on the second one! You need to go back and review the criterion for a function to be even if the hint given to you means nothing.

5. Originally Posted by skeeter
...
...i was looking for more of an expanded explaination

6. Originally Posted by clearlyjunk
...i was looking for more of an expanded explaination
... and I asked you to contribute to the problem by determining f(-x).

7. Originally Posted by skeeter and revised by Mr F
... and I asked you to contribute to the solution by determining f(-x).
Actually, I think you meant the above

Note to the OP: When a hint is given, it's expected that you make an effort to use the hint.

Edit: After sufficient time has passed to have properly thought about the hint I will re-open the thread.