STEP - BY - STEP EXPLANATION
What to find?
• Marginal cost as a function of q.
,• Revenue function in terms of q.
,• Marginal revenue function in terms of q.
Given:
[tex]\begin{gathered} p=105-\frac{q}{90} \\ \\ C\left(q\right)=22000+90q, \end{gathered}[/tex]Part A
Marginal cost as a function of q:
[tex]C^{\prime}(q)=\frac{d}{dq}(22000+90q)[/tex][tex]\begin{gathered} =0+90 \\ \\ =90 \end{gathered}[/tex]Part B
Revenue function in terms of q.
Revenue = pq
[tex]=(105-\frac{q}{90})q[/tex][tex]=105q-\frac{q^2}{90}[/tex]Hence;
[tex]R(q)=105q-\frac{q^2}{90}[/tex]Part C
Marginal revenue function in terms of q.
[tex]R^{\prime}(q)=\frac{d}{dq}(105q-\frac{q^2}{90})[/tex][tex]=105-\frac{2q}{90}[/tex][tex]=105-\frac{q}{45}[/tex]Hence;
[tex]R^{\prime}(q)=105-\frac{q}{45}[/tex]ANSWER
A) C'(q) =90
B) R(q) = 105q - q^2/90
C) R'(q) = 105 - q/45