Given f(x)=1/(7x-6) and g(x)=x/(x-7), find the domain of the composition (f o g)(x)
First of all, x-7/=0 --> x/=7. Also, 7(x/(x-7))/=6 --> 7x/=6x-42 --> x/=-42. So {x|x∈R,x≠7,x≠−42}
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