let x=
c(x)=
r(x)=
h(x)=
f(x)=
g(s)=
g(f(x))=
p(x)=
r(x)+c(x)
r(x)-c(x)
c(x)-r(x)
[r(x)][c(x)]
T(x)=
(10+x)-(2500-100x)
(10+x)+(2500-100x)
(10+x) (2500-100x)
(10+x) / (2500-100x)