Question 57352
a. Assume that Laffer's curve is given by R(x) = -6.5(x^3 + 2x^2 - 3x) / x^2+x+1 where R is measured in trillion of dollars. Use a graphing calculator to determine the tax rate x, to the nearest tenth of a percent, that would produce the maximum tax revenue. (Hint: Use a domain of [0,1] and a range of [0,4].) 
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Using a TI-83 I find x=0.39709951 or 0.397 or 39.7%
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b. Assume that Laffer's curve is given by R(x)= -1500(x^3+2x^2-3x)/x^2+x+400. Where R is measured in trillions of dollars. Use a graphing calculator to determine the tax rate x, to the nearest tenth of a percent, that would produce the maximum tax revenue.
0 solutions
x=0.53455305...=53.5%
Cheers,
Stan H.