function help?
\[Find (\frac{ f }{ g }) (x) for the functions provided: f(x) = x^2 − 9, g(x) = 3 − x\]
@Michele_Laino
here we have to evaluate the subsequent ratio: \[\frac{{{x^2} - 9}}{{3 - x}}\]
ok
i got x+3
now, we have to keep in mind that we can write the subsequent identity: \[{x^2} - 9 = \left( {x - 3} \right)\left( {x + 3} \right)\] so substituting in our ratio, we get: \[\frac{{{x^2} - 9}}{{3 - x}} = \frac{{\left( {x - 3} \right)\left( {x + 3} \right)}}{{ - \left( {x - 3} \right)}}\] since we have: 3-x=-(x-3) Please simplify, what do you get?
either x+3 or -x-3
oops i think im wrong
you can cancel similar terms
hint: |dw:1431631030840:dw|
oh i totally see it now
so, what is the result?
-x-3?
oh duh its x+3 because the others cancel out
there is -1 at the denominator
hint: |dw:1431631360001:dw|
at the numerator I have simplified by (x-3), namely I have computed this ratio: \[\frac{{\left( {x - 3} \right)}}{{\left( {x - 3} \right)}} = 1\] whereas at the denominator I have simplified by (x-3) too, so I have computed this ratio: \[\frac{{\left( {x - 3} \right)}}{{ - \left( {x - 3} \right)}} = - 1\]
ok
i still got -x-3 xD
that's right! -x-3= - (x+3)
so its f/g (x)= -x-3?
yes!
Yay! thanks again. P.s I really want to visit Italy :)
thanks! :)
and I really want to visit The United States of America! :)
ive heard that the food over there is amazing xD and p.s the american food is kind of gross. lol
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