tate the domain of the function f(x)=√X

Question

jhannybean · Answer

have you graphed it to see what the function looks like?

anonymous · Answer

oh ok but how would i do that..i mean i know how to graph but not square roots

jhannybean · Answer

Are you using a TI? Perhaps a TI-84?

anonymous · Answer

dont know what that is lol..tbh i barely learned anything this yr in MATH 3

jhannybean · Answer

If not, you can just try plugging in values for x. And because you cannot plug in negative values for x under a square root, you know your domain starts at 0. from x=0 onwards, you have increasingly larger values that keep going on and on. So, The domain for $$f(x)= \sqrt{x}$$ = $$0\le x \le \infty$$

anonymous · Answer

the function f(x) =$$\sqrt{x}$$ has the domain of positive real no union 0 or$$R ^{+}u0$$

anonymous · Answer

Ohhhh ok thank youu!

jhannybean · Answer

The reason you cannot plug negative values under a square root is because you will get imaginary numbers, you'll learn more about those later :)

anonymous · Answer

lol oh trust me i just learned how to do them lol i remember i = √-1 correct?

jhannybean · Answer

Actually.... the domain can be written as i mentioned above, OR like $$x \ge 0$$ haha. sorry about that!!

jhannybean · Answer

Yes you are right :)

anonymous · Answer

Yay! lol

anonymous · Answer

well thanks for you help
i might have another question soon lol

jhannybean · Answer

Alrighty :)

anonymous · Answer

oh wait i have this one more question..im on the next question..and i know how to do this problem --> (x+2)(2X²-3x+5)  but i just need to know when i multiply x*2x² is it 3x² or 2x³

jhannybean · Answer

It's $$2x^3 = (x)(2x^2) = (2)(1)(x ^{2+1})$$