Original function is
.
Replace x = 3 in original function.
\
(Evaluate power:
)
(Multiply:
)
(Subtract:
)
(Subtract:
)
Replace x = – 4 in original function.
\
Evaluate powers:
.

(Multiply:
)
(Subtract:
)
(Add: 256 + 16 = 272)
and
.