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#### Bose

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I just cant frickin figure this problem out and i have a ton of em due thursday can someone help me just figure one out then explain how you got the answer then i should be able to figure the rest out. here's the problem:

If f(x) = 3x, find the domain and range of function f.

#### Charger

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i think f(x) = 3x is y=3x if that helps

#### Charger

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i think the domain is x and the range is y so
domains : ranges
0 : 0
1 : 3
2 : 6
3 : 9

but not writen like that lol

#### stupidlikeaf0x

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The domain (x) and range are both all reals because the function is defined everywhere. Use a graphing calculator for harder ones if you have one because it really helps.

#### Bose

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so what your sayin is they are all real numbers????
and thanks boss_charger and stupidlikeaf0x i think i got it

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Bose said:
I just cant frickin figure this problem out and i have a ton of em due thursday can someone help me just figure one out then explain how you got the answer then i should be able to figure the rest out. here's the problem:

If f(x) = 3x, find the domain and range of function f.

f(x)=3x
Divide both sides by x
f=3
Now the range is the greatest number subtracted by the smallest number in a set of intergers.

Example:Find the range of these intergers [2,3,6,9,12,14]
14-2=12
Answer:The range of the intergers is 12

Although I am confused since there is only one number to represent f. So, I guess(but someone correct me if im wrong) the range would be 0.

After searching online for domain, it seems to apply only to linear equations(i.e. coordinate plane y=mx+b problems).

In New York Algebra and Geometry are mixed up into two 1.5 year courses that you take in 9-11 grade(although I started Math A in 8th since im accelerated) called Math A and Math B. I just started Math B after taking the Math A Regents in January so you may be learning stuff im not.

#### rory096

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i don't think that's right, because f isn't a variable, it's a function, so you can't just divide both sides by x.

#### Bose

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/\
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yea thats what i was thinkin

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forget it then, i thought i knew what i was doing but obviously i haven't learned this stuff yet

#### Charger

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F(x) is y

its the (Function of x ) or y

#### SoCalHomie

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Domain= all the possible values for x
Range= all posible values for y

Domain = (-infinite, +infinite)
range = (-infinite, +infinite)

this is an easy one but sometimes x or y can't equal a certain number. I'd try to explain but I think I would just confuse you. Try hotmath.com or drmath.com

#### BZ

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Its just all reals. simple as that. There is nothing that would make x or y undefined.

#### PimpNp8ntBaller

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damn, hard algebra 1, i took this last yr and we never did this, now im in geo, alot easier, but wouldnt a fraction or a negative make it undefined, kinda off topic i guess

#### sslecyk03

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no, the graph of y = 3x is a diagonal line that goes to negative infinity on the left and positive infinity on the right, negative infinity on the bottom and postitive infinity on top, so as ppl have said its all reals, there are no restrictions.

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BZSentinel said:
Its just all reals. simple as that. There is nothing that would make x or y undefined.
Bingo, and trust me, breezed thru math 115 with an A

#### chronic

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Woah Im in Algebra one and I havent learned this yet.... Im doin the whole y=mx+b thing. teh suck.

#### stupidlikeaf0x

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Oh, just wait til you get to Calculus.

#### Austin

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Basic math ownz. Yea I took basic last year now I'm in algebra. We are doin stuff like:

7x= 3x
3x+2 2x+4x

#### dhill0413

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f(x)=3x

the function of x is equal to 3 times x

the function of x can be reworded as 'y'

plug in your 'x' value into the equation, and you will come out with 3 times the 'x' value....whose product is your 'y' or function of x or f(x) value

simple...at least to me, honors pre-calculus sucks

#### PaiNtBaLLeR_200

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stupidlikeaf0x said:
Oh, just wait til you get to Calculus.
for real, i hate calculus.

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