SOLUTION: I kind of understand how to do these f◦g and g◦f problems, but I dont know how to do this one because the fraction throws me off. Please help me!!! Thank you!!!! The pr

Algebra ->  Inverses -> SOLUTION: I kind of understand how to do these f◦g and g◦f problems, but I dont know how to do this one because the fraction throws me off. Please help me!!! Thank you!!!! The pr      Log On


   

Question 100336: I kind of understand how to do these f◦g and g◦f problems, but I dont know how to do this one because the fraction throws me off. Please help me!!! Thank you!!!! The problem is:
For +f%28x%29=2x%2B1+ and +g%28x%29=%28x-1%29%2F2+, show that f ◦ g ( x ) = x and g ◦ f ( x) = x.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=2x+1 and g(x)=(x-1)/2
show that f ◦ g ( x ) = x and g ◦ f ( x) = x.
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fog(x)= f[g(x)] = f[(x-1)/2] = 2[(x-1)/2]+1 = (x-1)+1 = x
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gof(x) = g[f(x)] = g[2x+1] = ((2x+1)-1)/2 = 2x/2 = x
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Cheers,
Stan H.