Integrating Graphs with Two Intervals: How to Find the Mean?

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To integrate a function f(x) defined as k in two intervals (a, b) and (c, d), and zero elsewhere, the integral can be calculated as the sum of the integrals over the specified intervals. The total integral is k multiplied by the lengths of the intervals: k(b - a) + k(d - c). To find the mean value of f(x) over these intervals, divide the total integral by the combined length of the intervals, which is (b - a) + (d - c). This approach ensures that the mean accurately reflects the function's behavior across the defined regions. The discussion clarifies the integration process and the calculation of the mean for piecewise constant functions.
Dollydaggerxo
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In general,
if f(x)=k but only for a < x < b and c < x < d
how would you integrate the graph ?
To find the mean for example, would you find the mean for each and add together, or is there some special thing for this case?
 
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What's the value of f(x) for x not in the two intervals? Presumably the value is zero, but you didn't state this.

Assuming for the moment that f(x) = 0 outside the two intervals, finding the integral of this function (not the integral of its graph) is easy to find.
\int_{-\infty}^{\infty} f(x) dx~=~\int_a^b f(x) dx~+~\int_c^d f(x) dx~=~k(b - a)+ k(d - c)

To find the mean value of this function over the two intervals, evaluate the integral of the function (see above), and then divide by the length of the two intervals, b - a + d - c.
 
sorry, yes I meant if it is zero everywhere else.
Thanks
 
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