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determine the value of x to get the minimum value of f(x) by section search method ( only 4 iteration) and the initial guesses of lower is =15 and for upper = 20

A reversible chemical reaction 2A+B can be characterized by the equilibrium relationship K=ca2cbCc where the nomenclature cj represents the concentration of constituent i. Suppose that we define a variable x as representing the number of moles of C that are produced. Conservation of mass can be used to reformulate the equilibrium relationship as K=(ca,02x)2(cb,0x)(cc,0+x) where the subscript 0 designates the initial concentration of each constituent. Take K= 0.016,ca,0=42,cb,0=28, and cc,0=4