Final answer:
The instantaneous rate of change of the function f(x) at x=1 is found by calculating its derivative f'(x) and substituting x=1 into it, which results in f'(1) = 4.
Step-by-step explanation:
To find the instantaneous rate of change of the function f(x)=2x3-5x2+8x+1 at x=1 within the closed interval [1,3], we must calculate the derivative of f(x), which is f'(x). The derivative represents the instantaneous rate of change of the function at any point x.
The derivative f'(x) of the function f(x) is calculated as:
Power Rule: To differentiate xn, where n is a constant, multiply by the power and subtract one from the exponent.
Applying the power rule to each term in the function, we get:
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- f'(x) = d/dx (2x3) - d/dx (5x2) + d/dx (8x) + d/dx (1)
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- f'(x) = 6x2 - 10x + 8
Now, we substitute x=1 into f'(x) to get the instantaneous rate of change at that point:
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- f'(1) = 6(1)2 - 10(1) + 8
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- f'(1) = 6 - 10 + 8
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- f'(1) = 4
Therefore, the instantaneous rate of change of f(x) at x=1 is 4.