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Domain and Range of Composite Functions

Consider a function h(x)=x.
a) State the domain of h(x). {x| }
b) State the range of h(x). {y| }

Consider a composite function where f(x)=x2 and g(x)=x.
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f(g(x))=
f(g(x))=x but is the domain xR and the range yR?

a) Look at the diagram. State the domain of g(x). {x| }
b) Look at the diagram. State the range of g(x). {y| }
c) If these become the inputs for f(x), what is the range of (fg(x))? {y| }
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In summary, even though f(g(x))=x, the domain of f(g(x)) is {x| }
and the range of f(g(x)) is {y| }