Function Notation: If f(x) = 2x+1, g(x) = 3-x, find f(a),  TOPIC_SOLVED

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Re: Function Notation: If f(x) = 2x+1, g(x) = 3-x, find f(a),

Postby Martingale on Sun Apr 19, 2009 7:41 pm

jolie3000 wrote:Does this make more sense:
2f(x)=2(2x+1)=4x+2


this is correct
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Postby stapel_eliz on Sun Apr 19, 2009 7:42 pm

jolie3000 wrote:If ƒ(x) = 2x + 1, Find 2ƒ(x)
I originally worked it out like this:
ƒ(2(x))= 2(2(x)+ 1)

But 2 * f(x) is not at all the same thing as f(2*x). :shock: This is, in part, a result of the fact that the parentheses, in function notation, have nothing to do with multiplication. :wink:

jolie3000 wrote:Does this make more sense:
2f(x)=2(2x+1)=4x+2

Yes; two times f(x) means 2(f(x)) = 2(the formula for f) = 2(2x + 1).

Good job! :thumb:
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Re: Function Notation: If f(x) = 2x+1, g(x) = 3-x, find f(a),

Postby jolie3000 on Sun Apr 19, 2009 8:50 pm

YYYYYYYAAAAAAAA! thank you so very much for your help you guys. I am forever grateful :D :D
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