SOLUTION: Given f(x)= 6/x+7 and g(x)= 2/x-1 find (fg)(x) and its domain

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Question 63095: Given f(x)= 6/x+7 and g(x)= 2/x-1 find (fg)(x) and its domain
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Given f(x)= 6/x+7 and g(x)= 2/x-1 find (fg)(x) and its domain
%28fg%29%28x%29=%286%2F%28x%2B7%29%29%282%2F%28x-1%29%29
%28fg%29%28x%29=12%2F%28%28x%2B7%29%28x-1%29%29
The denominators are not allowed to =0 so the domain is x can = all real numbers except x cannot=-7,1.
Set builder notation {x|x not=-7,1}
Interval notation (-infinity,-7)U(-7,1)U(1,infinity)
Depending on your teacher or book you may have to foil the denominator.
%28fg%29%28x%29=12%2F%28x%28x-1%29%2B7%28x-1%29%29
%28fg%29%28x%29=12%2F%28x%5E2-x%2B7x-7%29
highlight%28%28fg%29%28x%29=12%2F%28x%5E2%2B6x-7%29%29
Happy Calculating!!!