The [[Riemann Integral|Riemann integral]] is the common definition today of the integral, as first put on a rigorous mathematical foundation by Riemann. The Riemann integral is, in essence, the definite integral:
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The [[Riemann Integral|Riemann integral]] is the common definition today of the integral in introductions to analysis, as first put on a rigorous mathematical foundation by Riemann. The Riemann integral is, in essence, the definite integral:
:<math>\int_a^b f(x)\,dx</math>
:<math>\int_a^b f(x)\,dx</math>
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It is defined as the sum of infinitesimal segments of the area under the function on a graph, between ''f(a)'' and ''f(b)''.
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It is defined as the sum of infinitesimal segments of the x-axis of the area under the function on a graph, between ''f(a)'' and ''f(b)''.
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As it is more versatile, the [[Lebesgue]] Integral has superseded this definition.