
Class
Meding
#19
-Let
c(x)and
R(x)
be
the
totar
cost
and
revenue
functions,
respectively.
-Then
theprofit
function
is
given
by,
n(x):
R(x)
_
C(x)
-T:.fo{
l(sales
quantiry)
formaximum
profit,
find
where
n,G):0.
S.ince
rc,(x):R,(x)
_
C,(*),
r
'(x) willoccur
where
R
,(x)
:
C
,(x).
Look
here
for
minimum
profit
also.
-R'(x):C
'(x)
is
where
marginal
revenue:
marginal
cost.
ffi*TR(x)
:5x
-
'003x2
and
c(x)
=
300
+
1.14
find
x
(number
of
units)
that
maximizes
profit
for
/ru/"t
c
T(x)
s
,?(x)-
Cftr)
s
9,?N
-,doty.\
7ao
77.?x)s
l,f
-
,aot% .=o
*
*=
6,fo
t"/il:
*,
oo
c
t(odo)
a
?aZ
f
IT(al
=
-.gao
fTftoaa)
s
Aao
<-
So,
)t
=e,fA
H-i
b?*in
*54.{4.,rfr*
-Note
thd
revenue
generated
equals
the
price
ofthe
item
sord
times
the
number
of
items
sord.
If
p:
the
price
of
each
item
ard
x
:
the
number
*iA,
irrJ
n1*;
:
p
".
-----
--
Example:
Let
x:rnrmber
ofpeople
attending
an
event
and
p:
70_
02x
be
the price
of
a
ticket.
As
the
number
attendingincreases'
the price
otttt*t,
?1
ur
th.
p;;;;r"ases,
the
numbei
attending
decreases
(makes
more
sense)'
Find
a)
the
tolal
t"t'"n"t,
R(^)
'b).the
*""oi;,
iflJoo
u,r*a,
,)
il;;;"dance
that
maximLes
revenue,
fl,5
Bffi:Tf:X*:ffi,
"r-,i"?;_;*;;;;:
;;rru
ii
til;;;;;,,
how
much
pront
do you
e)
fttxt=
Y'*=
(za-,o1'r.)t'x
s
?oX-,o47L
"e\
RtSaao):
3a.,ooo
e)
Rtx\r?o-,o')2.
so
-+
?1
sl?,fo
/)
ys
?o-.03(tz,fo)s3d
e)
Rttr{o)s
Lt,&fa
4)
?rr.t
Zua(
b74,-v&.
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