Question 207971
I would to ask on how to solve this problem: 
Given f = {(-2,3),(-1,1),(0,0),(1,-1),(2,-3)} and
g = {(-3,1),(-1,-2),(0,2),(2,2),(3,1)} 
please find 
a.) (fog)(0)= f[g(0)] = f[2] = -3

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and (gof)(-1)= g[f(-1)} = g[1] = ?
Can't answer that because g(1) is not defined.
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Cheers,
Stan H.