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Question
Let f and g be two real functions given by
f = {(0, 1), (2, 0), (3, −4), (4, 2), (5, 1)} and g = {(1, 0), (2, 2), (3, −1), (4, 4), (5, 3)}
Find the domain of fg.
Solution
It is given that f and g are two real functions such that
f = {(0, 1), (2, 0), (3, −4), (4, 2), (5, 1)}
and g = {(1, 0), (2, 2), (3, −1), (4, 4), (5, 3)}
Now,
Domain of f = Df = {0, 2, 3, 4, 5}
Domain of g = Dg = {1, 2, 3, 4, 5}
∴ Domain of fg = Df ∩ Dg = {2, 3, 4, 5}
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