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Example 2

Plot the function:

Step 1

No singularity

Step 2

Calculation of f ' and f"

f(x) = x3 -3x2+1

f '(x) = 3x2 - 6x

f"(x) = 6x - 6

Step 3

f '(x) = 3x2 - 6x

        = 3x(x-2)

f '(x) = 0 for x = 0 or x = 2 (critical points)

f(0) = 1 and f(2) = -3 (critical values)

f '(x) > 0 for x < 0 and x > 2

f is increasing for x < 0 and x > 2

f '(x) < 0 for 0 < x < 2

f is decreasing for 0 < x < 2

Step 4

f"(x) = 6x - 6

f"(x) = 0 for x = 1 (inflection point)

f"(x) < 0 for x < 1

f is concave down for x < 1

f"(x) > 0 for x > 1

f is concave up for x > 1