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Concavity question (1 Viewer)
- Thread starter BlueGas
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DatAtarLyfe
Booty Connoisseur
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- 2016
If you've drawn the graph correctly, you can inspect which parts are concave down and draw tangents at each point. Wherever you drew negative gradients on the concave down parts would be your solution.
Alternatively, you can differentiate f(x) and make f'(x) < 0 to identify the values that have a negative gradient ie decreasing. Then differentiate it again and make f"(x) < 0 to identify which parts the function is concave down. If you graph the two inequalities, wherever they overlap is where the original f(x) is concave down AND decreasing
Alternatively, you can differentiate f(x) and make f'(x) < 0 to identify the values that have a negative gradient ie decreasing. Then differentiate it again and make f"(x) < 0 to identify which parts the function is concave down. If you graph the two inequalities, wherever they overlap is where the original f(x) is concave down AND decreasing
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That's what I got as well, so I'm assuming it's right.