Calculus
Intermediate

Definite Integral (Area)

The net area between a curve and the x-axis from a to b.

Formula

∫abf(x) dx=signed area under f\int_a^b f(x)\,dx = \text{signed area under } f

Variables

fFunction
a, bLimits

Example

∫₀³ x dx equals the area of a triangle: ½·3·3 = 4.5.

Did You Know?

A definite integral is a signed area — regions below the axis count as negative.

integralarea