Calxsolver
Calculus

Definite Integral

Enter a function of x and the interval limits a and b. The calculator approximates the definite integral — the signed area under the curve — using composite Simpson's rule, which is accurate even for curved functions.

Definite Integral

Numeric definite integral of any function of x.

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Frequently asked questions

What method is used?

Composite Simpson's rule with 1000 subintervals, which fits the curve with parabolic segments for high accuracy.

Can the result be negative?

Yes. The definite integral is a signed area, so regions below the x-axis contribute negative values.

What functions are supported?

Any expression in x, including trigonometric, exponential, logarithmic and rational functions.

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