supose the following demand and cost function of duopoly firm

x=40-0.2p where x=x1+x2
c1=50+2x1+0.5x12
c2=100+10x2
drive riaction function
find cournot equilibrium quantity and price
calculate the equilubrium price and output of each firm assume firm 1 is sophisticated and firm 2 is follower firm?

32

i have not a response

TC=20 P=10

Do it

x=40-0.2p, x=x1 +x2, c1 =50+2x1 +0.5x1², C2 =100+0.2P2

a, derived the isoproft function of each firm
b,derived the reaction function of each firm

45

Student

answer

a) Isoprofit function of firm 1:

Profit (𝜋) = Total revenue (TR) – Total cost (TC)

Total revenue (TR) = Price (p) x Quantity (x1) = p*x1

Total cost (TC) = 50 + 2x1 + 0.5x1²

Profit (𝜋) = p*x1 - (50 + 2x1 + 0.5x1²)

Isoprofit function of firm 1:

𝜋1 = p*x1 - (50 + 2x1 + 0.5x1²)

Isoprofit function of firm 2:

Profit (𝜋) = Total revenue (TR) – Total cost (TC)

Total revenue (TR) = Price (p) x Quantity (x2) = p*x2

Total cost (TC) = 100 + 10x2

Profit (𝜋) = p*x2 - (100 + 10x2)

Isoprofit function of firm 2:

𝜋2 = p*x2 - (100 + 10x2)

b) Reaction function of firm 1:

For a given price (p), firm 1’s profit-maximizing output (x1) can be obtained by setting the derivative of 𝜋1 with respect to x1 equal to zero and solving for x1:

𝜋1 = p*(40-0.2p-x2) - (50 + 2*(40-0.2p-x2) + 0.5*(40-0.2p-x2)²)

Taking the derivative of 𝜋1 with respect to x1:

d𝜋1/dx1 = -p - 2 - (40-0.2p-x2)*0.5*(d/dx2)(40-0.2p-x2)

Setting d𝜋1/dx1 equal to zero and solving for x1:

d𝜋1/dx1 = -p - 2 - (40-0.2p-x2)*0.5*(-0.2) = 0

0.1(40-0.2p-x2) = -p - 2 - 4

0.1x1 = -p - 6 - x2

x1 = -10p - 60 - 10x2

Reaction function of firm 1:

x1 = -10p - 60 - 10x2

Reaction function of firm 2:

For a given price (p), firm 2’s profit-maximizing output (x2) can be obtained by setting the derivative of 𝜋2 with respect to x2 equal to zero and solving for x2:

𝜋2 = p*(40-0.2p-x1-x2) - (100 + 10x2)

Taking the derivative of 𝜋2 with respect to x2:

d𝜋2/dx2 = -p - 10 + (40-0.2p-x1-x2)*(-1)

Setting d𝜋2/dx2 equal to zero and solving for x2:

d𝜋2/dx2 = -p - 10 + 40 + 0.2p + x1 + x2 = 0

x2 = -p + 30 - 0.1x1

Substituting the reaction function of firm 1 into the reaction function of firm 2:

x2 = -p + 30 - 0.1(-10p - 60 - 10x2)

x2 = -1p + 24 - x2

2x2 = -1p + 24

x2 = -0.5p + 12

Reaction function of firm 2:

x2 = -0.5p + 12

calculate the profit of each firm