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Find the point of inflection of the graph of the function f(x)=8−5x4. Determine the open intervals on which the graph is concave upward and concave downward.

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Final answer:

The point of inflection of the graph of the function f(x) = 8 - 5x^4 is (0, 8). The graph is concave downward for x < 0 and concave upward for x > 0.

Step-by-step explanation:

To find the point of inflection of the graph of the function f(x) = 8 - 5x^4, we need to find the second derivative and set it equal to zero.

The first derivative of f(x) is f'(x) = -20x^3 and the second derivative is f''(x) = -60x^2.

Setting f''(x) = 0, we get -60x^2 = 0, which implies x = 0.

So, the point of inflection is (0, 8).

The graph of the function f(x) = 8 - 5x^4 is concave upward when the second derivative is positive, and concave downward when the second derivative is negative.

Since f''(x) = -60x^2, it is negative for x values less than 0 and positive for x values greater than 0.

Therefore, the graph is concave downward for x < 0 and concave upward for x > 0.

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