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Brynlee
08-22-2013, 06:58 PM
If f(x)=-x+4 and f(h(2))=10, which of the following could be the function h(x).


(A) h(x)=-x+4
(B) h(x)=5x
(C) h(x)=-2x-2
(D) h(x)=-6x
(E) h(x)=10


Thanks:D:D

Jack
08-22-2013, 07:00 PM
Function composition is a way of combining functions such that the result of each function is passed as the argument of the other function. (f\circ h)(x)= f(h(x))

f(h(2))=10 \Rightarrow -h(2)+4=10 \Rightarrow h(2)=-10+4=-6 (1)

The only function from (A)-(E) that satisfy the equality (1) is choice (C) h(x)=-2x-2

since h(x)=-2x-2=-2(2)-2=-4-2=-6.

Brynlee
08-22-2013, 07:02 PM
:DThank you Jack!!:D