1) Let the function of be defined by f (x) = 5x3 + 6x2 - 3x + 1 for all real numbers I' E (-0o, co) . This function has two critical values. One of the critical values is negative and the other is positive. Fill in the following blanks with a decimal if the answer is not an integer or with an integer if the answer is an integer. Give exact answers. a) The negative critical value is b) The positive critical value is c) The relative minimum is d) The relative maximum is For the next two questions, type yes if your answer is yes and type no if your answer is no. e) Is the derivative f (@) positive on the interval (-co, -1)? f) Is the derivative f' (x) positive on the interval (-1, 0.2)