Page 56 - Calc for the Clueless
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We will test for the cusp first or second kind of inflection point.

        1. f'(2)= infinity

        2. f(2) = 3 (2,3)

                               +
              -
        3. f'(2 ) is negative, f'(2 ) is positive. Cusp with the point down.
                                    4/5
                                             1/5
        x intercept: y = 0.-3 = (x - 2) . (x - 2)  = ±(-3) , which is imaginary. No x intercepts, y intercept: x = 0. y =
                                                       1/4
                         4/5
            4/5
        (-2)  + 3. [0,(-2)  + 3] = A. No round max or min and no inflection points, f(1000) is positive and f(-1000) is
        positive. Both ends go to plus infinity. The sketch:




















        Example 28—








        Intercept (0,0). No round max or min and no inflection points.

        1. |f'(0)| = infinity

        2. f(0) = 0

              -
                    +
        3. f'(0 ), f'(0 ) both positive. Second kind of inflection point.
        4. f(100,000) positive and f(-100,000) negative. The right end goes to plus infinity and the left end goes to
        minus infinity.

        The sketch:













        Instructors have been known to give messy examples. While I know yours would never give one, here are two
        that will take time.

        Example 29—
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