josemnz83 wrote:
For which of the following functions does f(x)=f(2-x)?
A. f(x)=x+2
B. (fx)=2x-x^2
C. f(x)=2-x
D. f(x)=(2-x)^2
E. f(x)=x^2
Answer choice C seems to work out if we plug in 1 for x. Did I do something wrong or must the function be true for all values? C does not work for a value of x=4?
f(x)=2-1=1
f(x)= 2-(2-x).....>2-(2-1).....>2-(1) = 1
hi,
in all the option just put 2-x in place of x
A. f(x)=x+2===>f(2-x)=2-x+2=4-x==>not equal
B. (fx)=2x-x^2====>f(2-x)=2(2-x)-(2-x)^2=4-2x-x^2+4x-4=2x-x^2===>equal==correct
C. f(x)=2-x===>f(2-x)=2-(2-x)=x===>not equal
D. f(x)=(2-x)^2===>f(2-x)=(2-2+x)^2=x^2===>not equal
E. f(x)=x^2===>f(2-x)=(2-x)^2===>not equal
hence only B satisfies.
dont plug in this
hope it helps.
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