help with operations with functions  TOPIC_SOLVED

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help with operations with functions

Postby isaiah45798 on Sun Jul 17, 2011 12:08 am

Ok so f(x)={(3,5)(2,4)(1,7)}, and g(x)=sqrt(x-3). I have to figure out (f+g)(1). Any ideas? Thanks in advance.
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Re: help with operations with functions

Postby little_dragon on Sun Jul 17, 2011 1:22 am

isaiah45798 wrote:Ok so f(x)={(3,5)(2,4)(1,7)}, and g(x)=sqrt(x-3). I have to figure out (f+g)(1). Any ideas? Thanks in advance.

wat is f(1)? (get this from the set of pts)
wat is g(1)? (get this from the fcn)
add to get f(1)+g(1)=(f+g)(1)
U can learn more here: http://www.purplemath.com/modules/fcnops.htm

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Re: help with operations with functions

Postby isaiah45798 on Sun Jul 17, 2011 1:34 am

Thank you very much. I have two more questions if someone is willing to help. Using the same f(x), how would I go about solving 1/f(x). And if k(x)=x^2+5 and g(x)=sqrt(x-3) how would I figure out (kg)(x).
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Re: help with operations with functions

Postby little_dragon on Sun Jul 17, 2011 8:59 pm

do just like it shows in the link!!
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Re: help with operations with functions

Postby isaiah45798 on Sun Jul 17, 2011 11:57 pm

ok so that helped alot but i am having trouble understanding how to do the function operation with 1/f(x) due to the fact that f(x) has a list of points, f(x)={(3,5)(2,4)(1,7)}.
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Re: help with operations with functions

Postby little_dragon on Mon Jul 18, 2011 12:31 am

isaiah45798 wrote:ok so that helped alot but i am having trouble understanding how to do the function operation with 1/f(x) due to the fact that f(x) has a list of points, f(x)={(3,5)(2,4)(1,7)}.

wat does f(3) equal? so wat is 1/f(3)?
do same w/ other 2 pts
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Re: help with operations with functions  TOPIC_SOLVED

Postby isaiah45798 on Mon Jul 18, 2011 1:55 am

so would it be 1/5,1/4,1/7. and by the way thankyou
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