SOLUTION: f(x)=2x3 − 4x2 +3x − 5 for which x values is the graph concave down?

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Question 1057331: f(x)=2x3 − 4x2 +3x − 5
for which x values is the graph concave down?
Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
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f(x) = 2x^3 - 4x^2 +3x - 5
for which x values is the graph concave down?
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The first derivative of f(x) is f'(x) = 6x%5E2+-+8x+%2B+3.

The second derivative of f(x) is f''(x) = 12x-8.

The graph is concave down  <----->   f''(x) < 0,   i.e.

12x - 8 < 0 <---> x < 8%2F12 = 2%2F3.



Plot y = 2x%5E3+-+4x%5E2+%2B3x+-+5