William W. answered • 04/12/23
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A = 1∫9 1/x dx = ln(x) evaluated between 1 and 9 = ln(9) - ln(1) = ln(9) sq units (approx 2.1972 sq units)
William W.
The area under the curve is the integral of f(x). To calculate the integral, you find the antiderivative of 1/x. That would be the function, that if you took its derivative, would give you 1/x as the result. The antiderivative of 1/x is ln(x), again, because when you take the derivative of ln(x), you get 1/x. To evaluate the definite integral, you evaluate the antiderivative at the endpoints and subtract them.
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04/12/23
William W.
If you have a TI-84 calculator, you can just use the calculator. Use the "math" button and scroll down to "fnInt(" (number 9 on my calculator) and enter the function 1/x dx with the two endpoints, 9 on top and 1 on bottom. But it just gives the approximation answer not the exact value of ln(9)
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04/12/23
Jj M.
wouldnt it have to fit in this? f(x)=1/x04/12/23