Answer:
<u>Rule for rotation 180° about the origin:</u>
<u>Given coordinates:</u>
<u>Coordinates of the image, apply the rule above:</u>
Dom(gof)=Dom(f)={1,3,4}.
(gof)(1)=g{f(1)}=g(2)=3.
(gof)(3)=g{f(3)}=g(5)=1.
(gof)(4)=g{f(4)}=g(1)=3.
∴gof={(1,3),(3,1),(4,3)}.
a
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b + 2