Question

A firm's average revenue function 

𝐴𝑅=−18−7,5𝑄+𝑄

2

.

AR=−18−7,5Q+Q2.

Find the TR and 𝑀𝑅 functions.

a.

=−18𝑄−7,5𝑄2+𝑄3=−18Q−7,5Q2+Q3

b.=−18𝑄−7,5𝑄2+𝑄3=−18Q−7,5Q2+Q3

c.=−18−7,5𝑄+𝑄2=−18−7,5Q+Q2

d.=−18−7,5𝑄+𝑄2=−18−7,5Q+Q2

Answer 1

If $AR = −18 − 7.5Q + Q^2$ , then:

$TR = AR×Q = −18Q − 7.5Q^2 + Q^3$ ,

$MR = TR'(Q) = -18 - 15Q + 3Q^2$ .

So, the correct answer is a or b.