Answer
$ J_{5} = \left \{ 0, 1, 2, 3, 4 \right \},
f :J_{5}\rightarrow J_{5}
\,\,and\,\, g :J_{5}\rightarrow J_{5}\\
f (x)=(x + 4)^{2}\,\,mod\,\,5\,\,and\,\,g(x)=(x^{2} + 3x + 1)\,\,mod\,\,5.\\
f(0)=(0+4)^2\,\,mod\,\,5=16\,mod\,5=1\\
f(1)=(1+4)^2\,\,mod\,\,5=25\,mod\,5=0\\
f(2)=(2+4)^2\,\,mod\,\,5=36\,mod\,5=1\\
f(3)=(3+4)^2\,\,mod\,\,5=49\,mod\,5=4\\
f(4)=(4+4)^2\,\,mod\,\,5=64\,mod\,5=4\\
g(0)=(0^{2} + 3(0) + 1)\,\,mod\,\,5=1\,mod\,5=1\\
g(1)=(1^{2} + 3(1) + 1)\,\,mod\,\,5=5\,mod\,5=0\\
g(2)=(2^{2} + 3(2) + 1)\,\,mod\,\,5=11\,mod\,5=1\\
g(3)=(3^{2} + 3(3) + 1)\,\,mod\,\,5=19\,mod\,5=4\\
g(4)=(4^{2} + 3(4) + 1)\,\,mod\,\,5=29\,mod\,5=4\\
so\,\,\\
f(0)=g(0)=1 \\
f(1)=g(1)=0 \\
f(2)=g(2)=1 \\
f(3)=g(3)=4 \\
f(4)=g(4)=4 \\
\therefore f=g
$
Work Step by Step
$ J_{5} = \left \{ 0, 1, 2, 3, 4 \right \},
f :J_{5}\rightarrow J_{5}
\,\,and\,\, g :J_{5}\rightarrow J_{5}\\
f (x)=(x + 4)^{2}\,\,mod\,\,5\,\,and\,\,g(x)=(x^{2} + 3x + 1)\,\,mod\,\,5.\\
f(0)=(0+4)^2\,\,mod\,\,5=16\,mod\,5=1\\
f(1)=(1+4)^2\,\,mod\,\,5=25\,mod\,5=0\\
f(2)=(2+4)^2\,\,mod\,\,5=36\,mod\,5=1\\
f(3)=(3+4)^2\,\,mod\,\,5=49\,mod\,5=4\\
f(4)=(4+4)^2\,\,mod\,\,5=64\,mod\,5=4\\
g(0)=(0^{2} + 3(0) + 1)\,\,mod\,\,5=1\,mod\,5=1\\
g(1)=(1^{2} + 3(1) + 1)\,\,mod\,\,5=5\,mod\,5=0\\
g(2)=(2^{2} + 3(2) + 1)\,\,mod\,\,5=11\,mod\,5=1\\
g(3)=(3^{2} + 3(3) + 1)\,\,mod\,\,5=19\,mod\,5=4\\
g(4)=(4^{2} + 3(4) + 1)\,\,mod\,\,5=29\,mod\,5=4\\
so\,\,\\
f(0)=g(0)=1 \\
f(1)=g(1)=0 \\
f(2)=g(2)=1 \\
f(3)=g(3)=4 \\
f(4)=g(4)=4 \\
\therefore f=g
$