Determine algebraically whether the function is even, odd, or neither even nor odd.
Medal rewarded
@Yttrium
How do you differentiate function that is even, odd or neither even nor odd?
I dont know, thats why im asking. I am posting a few questions on a practice exam that i dont know the answers two, its doesn't count for anything, just a way to study.
Could you tell me what the answer is and why?
Please, im kind of in a hurry.
Simplify f(-x). If f(-x)=f(x), then it is even. If f(-x)=-f(x), then it is odd. If f(-x) is not equal to either of those, then it's neither.
Just plug in -x into the equation, and see if it will come up with this conditions: 1. Direct opposite. Hence, that is odd. 2. The same. Hence, that is even. 3. Not direct opposite nor same. Neither even nor odd.
Do you get it now @MandyNeedsHelp ?
Is it odd?
No. Simplify first the expression. Find the LCD to avoid fractions.
Thats why i cant find this one because i dont know how with a fraction
Wait - are we looking at the same problem, @Yttrium ? f(x)=x+4/x ?? f(-x)=-x+4/(-x) = -x-4/x=-(x+4/x)??
Multiply this by x, to cancel the denom x in the second term, right? \[x [x+\frac{ 4 }{ x }]\] Hence, \[f(x)x^2+4\] Now, insert (-x) and see what will happen. I think so @DebbieG
I mean \[f(x) = x^2 +4\]
Wait, is this neither?
It's actually even. :)
Wanna know why?
yes i do lol
You can't multiply a function by x!! You can multiply it by x/x. but if you multiply it by x, it's a DIFFERENT function than what you started with.
The fraction shouldn't be a problem for determining oddness or evenness, just see what I did above. But, if you don't like the fraction, then by all means, write over LCD of x: \(\large f(x)=\dfrac{x^2+4}{x}\) Then again: \(\large f(-x)=\dfrac{(-x)^2+4}{-x}=\dfrac{x^2+4}{-x}=-\left(\dfrac{x^2+4}{x}\right)=-f(x)\)
Just look at the graph: https://www.desmos.com/calculator/kt2ih5gevg Odd, for sure.
Compare to \(y=x^2+4\): https://www.desmos.com/calculator/74ryzng7e7 Not the same function.
Oh I forgot to write the denom. That's what I really wanna say. HAHA. Thanks @DebbieG
Thank you both so much!!!
you're welcome. :)
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