Practice

Problems

for

Exam

#2

1) R(x)

=

625'lI

lx-I5x3

Represents

tlte revenue

for

the

sale

ofx

units

of

a

given

item

and

C(x)

:

(t/4)x4

-63ox2

-99ox+700

represents

the

total

cost

of

production

of x

units.

a)

Find

the

profit,

p(x),

when

x

units

of that

item

are

sold in

simplest

form.

b)

Compute

P'(x)

,

C'(x)

and

p,,(x)

P'(x)

=

P"(x)

=

c'(x):

c)

Find

the marginal

profit

atpl2

d) Find

the

marginal

cost

at:rl2

2)

The

revenue

function

for

a

given

firm

is

R(x)

=

7a09(.x_5)

r.

Find

the rate

of

change

*'+

9

of R

with

respect

to

x

at :r

?