polynomial functions...

Question

anonymous · Answer

$$x2\sqrt{2}+x-5$$   The question is "is this a polynomial function" and if yes why?

precal · Answer

precal · Answer

maybe this will help you

anonymous · Answer

Hum...I understand the expression; it's the $$x ^{2}\sqrt{2}$$ part that is tripping me up.

anonymous · Answer

$$f(x) =X^{2}\sqrt{2}+x-5$$

precal · Answer

square root of 2 is just a number correct?
1.4142x^2+x-5

precal · Answer

so what do you think? is it or isn't it?

anonymous · Answer

based on theory I would say no; since it's an irrational radical

anonymous · Answer

or in other words it's not a perfect sq

precal · Answer

that has nothing to do why it is polynomial

precal · Answer

it is a polynomial

precal · Answer

now if it was like this it would not be|dw:1357607467019:dw|

anonymous · Answer

i know it's a polynomial i need to know if its a POLYNOMIAL FUNCTION

precal · Answer

|dw:1357607478854:dw|because the power of x is 1/2 and you can not have a fraction as a power

precal · Answer

graph it

anonymous · Answer

OK THANKS :)

precal · Answer

|dw:1357607550237:dw|looks like a function to me, especially since it passes the vertical line test

anonymous · Answer

thanks for the help; graphed it and got the same.  Its a quadratic function;)

precal · Answer

yes and quadratics are polyominals
yw