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Solve for the optimal values of C1 and C2 in the following optimization problem: MaxC1,C2√C1+β√C2 s.t. C1+ C2/1+r =Y1+Y2/1+r

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To solve the optimization problem, let's define the objective function and the constraint equation in a more explicit manner:

Objective function:

f(C1, C2) = √C1 + β√C2

Constraint equation:

C1 + C2/(1+r) = Y1 + Y2/(1+r)

Now, let's proceed with solving the problem.

Step 1: Rewrite the constraint equation

Multiply both sides of the constraint equation by (1+r) to eliminate the denominator:

(1+r)(C1 + C2/(1+r)) = (1+r)(Y1 + Y2/(1+r))

C1 + C2 + C2r/(1+r) = (1+r)Y1 + Y2

Step 2: Express C1 in terms of C2

C1 = (1+r)Y1 + Y2 - C2 - C2r/(1+r)

Step 3: Substitute the expression for C1 into the objective function

f(C2) = √[(1+r)Y1 + Y2 - C2 - C2r/(1+r)] + β√C2

Step 4: Differentiate the objective function with respect to C2

f'(C2) = -1/2[(1+r)Y1 + Y2 - C2 - C2r/(1+r)]^(-1/2) - 1/2βC2^(-1/2)

Step 5: Set the derivative equal to zero and solve for C2

-1/2[(1+r)Y1 + Y2 - C2 - C2r/(1+r)]^(-1/2) - 1/2βC2^(-1/2) = 0

Simplifying the equation:

[(1+r)Y1 + Y2 - C2 - C2r/(1+r)]^(-1/2) = -βC2^(-1/2)

Squaring both sides:

[(1+r)Y1 + Y2 - C2 - C2r/(1+r)]^(-1) = β^2C2^(-1)

Taking the reciprocal of both sides:

[(1+r)Y1 + Y2 - C2 - C2r/(1+r)] = β^2C2

Simplifying further:

(1+r)Y1 + Y2 - C2 - C2r/(1+r) = β^2C2

Rearranging the equation:

(1+r)Y1 + Y2 = (1+β^2)C2 + C2 + C2r/(1+r)

Step 6: Express C2 in terms of Y1, Y2, and r

C2 = [(1+r)Y1 + Y2]/[(1+β^2) + (1+r)(1+β^2)]

Step 7: Substitute the expression for C2 back into the constraint equation to solve for C1

C1 = Y1 + Y2 - C2 - C2r/(1+r)

With the obtained expressions for C1 and C2, you have the optimal values for C1 and C2 in the given optimization problem.


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