If x subscript 1 and x subscript 2 are the number of items of two goods bought, a customer’s utility is upper u left-parenthesis x subscript 1 baseline comma x subscript 2 baseline right-parenthesis equals 2 x subscript 1 baseline x subscript 2 baseline plus 3 x subscript 1. the unit cost is dollar-sign baseline 1 for the first good and dollar-sign baseline 3 for the second. use lagrange multipliers to find the maximum value of upper u if the consumer’s disposable income is dollar-sign 106. estimate the change in optimal utility if the consumer's disposable income increases by dollar-sign 9.