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Problem 3.(45 Relative Points) Given the Vasko Popov method with the equation q (x) = x - [(x) S'(a) on the interval [a, b]ED, . Assume that: 1) f"(x) , f' (x) and f(x) continuous on [a,b]; 2) f(a) > 0, f(alf"(a) >0; 3) f" (x) and f'(x) do not change sign on [a, b]; 4) sign(f (a)) + sign((fb)). Prove that (q'(x) |