Mathematics · Calculus

Definite Linear Integral Calculator

Integrate mx+b over a finite interval.

Runs locally
Your numbers

Inputs and results stay in this browser. Change one value at a time to explore the relationship.

Your inputCalculatedPassed forward in chains
Definite integral12
Upper antiderivative12
Lower antiderivative0

Calculation steps

  1. F(x)=2x²/2+1x.
  2. F(3)−F(0)=12.

Understand Definite linear integral

One idea, three depths

Choose how deeply to explain Definite linear integral

Definite linear integral: Integrate mx+b over a finite interval.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Definite linear integral to answer this question: integrate mx+b over a finite interval? Enter Slope m, Intercept b, Lower bound, and 1 other input; the calculator shows Definite integral. For example: Integral of 2x+1 from 0 to 3 is 12. The answer tells you Definite integral.

Age 15Explain it to a 15-year-oldConnect it to the formula

The definite integral accumulates signed area under the line. The rule is ∫(mx+b)dx=[mx²/2+bx]. Its input values are Slope m, Intercept b, Lower bound, Upper bound, and the main result is Definite integral. For example: Integral of 2x+1 from 0 to 3 is 12.

CollegeExplain it at college levelState the model precisely

This calculator evaluates the stated definite linear integral relation over the valid real-number domain stated below. The implemented relation is ∫(mx+b)dx=[mx²/2+bx], evaluated from Slope m, Intercept b, Lower bound, Upper bound to produce Definite integral. The definite integral accumulates signed area under the line. Area below the x-axis contributes negatively to a signed integral.

Inputs and valid domain

  • Slope m must be a finite real number.
  • Intercept b must be a finite real number.
  • Lower bound must be a finite real number.
  • Upper bound must be a finite real number.

Important boundary: Area below the x-axis contributes negatively to a signed integral.

The formula

∫(mx+b)dx=[mx²/2+bx]

How the calculator works through it

It substitutes Slope m, Intercept b, Lower bound, Upper bound into the formula and exposes every numerical step above. The main output is Definite integral, accompanied by Upper antiderivative, Lower antiderivative.

Read the result correctly

The Definite integral is the direct answer to “integrate mx+b over a finite interval.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.

A worked check

Integral of 2x+1 from 0 to 3 is 12.

Where this model stops being reliable

Area below the x-axis contributes negatively to a signed integral.

Learn it by changing one value

Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.

Dictionary terms behind this calculator

Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.

These foundations help you understand why Definite linear integral works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.

Hard requirements

  • Reading formulas and substituting values

    Definite linear integral uses ∫(mx+b)dx=[mx²/2+bx]. You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.

    Review this foundation about 4 min

Strong support

Optional enrichment

Learn the missing foundationsI already know these — show the code

Mathematics → algorithm → program

Implement this calculation in code

These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.

Algorithm

  1. Read Slope m, Intercept b, Lower bound, Upper bound.
  2. Evaluate the principal relationship: ∫(mx+b)dx=[mx²/2+bx].
  3. Return Definite integral and check the domain conditions described above.
Python
            from math import *

def definite_linear_integral(a, b, x1, x2) -> float:
    return ((((a * (x2 * x2)) / 2.0) + (b * x2)) - (((a * (x1 * x1)) / 2.0) + (b * x1)))

assert abs(definite_linear_integral(2, 1, 0, 3) - 12) < 1e-6 * max(1.0, abs(12))
          
Current calculator valuesUpdates when you change an input above.
              
            
C
            #include <assert.h>
#include <math.h>

double definite_linear_integral(double a, double b, double x1, double x2) {
    return ((((a * (x2 * x2)) / 2.0) + (b * x2)) - (((a * (x1 * x1)) / 2.0) + (b * x1)));
}

int main(void) {
    const double expected = 12;
    const double actual = definite_linear_integral(2, 1, 0, 3);
    assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
C++
            #include <cassert>
#include <cmath>
#include <numbers>

double definite_linear_integral(double a, double b, double x1, double x2) {
    return ((((a * (x2 * x2)) / 2.0) + (b * x2)) - (((a * (x1 * x1)) / 2.0) + (b * x1)));
}

int main() {
    constexpr double expected = 12;
    const double actual = definite_linear_integral(2, 1, 0, 3);
    assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
Linux x86-64 assembly

x86-64 NASM · System V ABI · Linux · SSE2 with libm where required

            ; double definite_linear_integral(double a, double b, double x1, double x2)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
global definite_linear_integral
section .text

definite_linear_integral:
    push rbp
    mov rbp, rsp
    sub rsp, 144
    movsd [rbp-8], xmm0
    movsd [rbp-16], xmm1
    movsd [rbp-24], xmm2
    movsd [rbp-32], xmm3
    movsd xmm0, [rbp-32]
    mulsd xmm0, [rbp-32]
    movsd [rbp-72], xmm0
    movsd xmm0, [rbp-8]
    mulsd xmm0, [rbp-72]
    movsd [rbp-64], xmm0
    mov rax, 0x4000000000000000
    movq xmm0, rax
    movsd [rbp-80], xmm0
    movsd xmm0, [rbp-64]
    divsd xmm0, [rbp-80]
    movsd [rbp-56], xmm0
    movsd xmm0, [rbp-16]
    mulsd xmm0, [rbp-32]
    movsd [rbp-88], xmm0
    movsd xmm0, [rbp-56]
    addsd xmm0, [rbp-88]
    movsd [rbp-48], xmm0
    movsd xmm0, [rbp-24]
    mulsd xmm0, [rbp-24]
    movsd [rbp-120], xmm0
    movsd xmm0, [rbp-8]
    mulsd xmm0, [rbp-120]
    movsd [rbp-112], xmm0
    mov rax, 0x4000000000000000
    movq xmm0, rax
    movsd [rbp-128], xmm0
    movsd xmm0, [rbp-112]
    divsd xmm0, [rbp-128]
    movsd [rbp-104], xmm0
    movsd xmm0, [rbp-16]
    mulsd xmm0, [rbp-24]
    movsd [rbp-136], xmm0
    movsd xmm0, [rbp-104]
    addsd xmm0, [rbp-136]
    movsd [rbp-96], xmm0
    movsd xmm0, [rbp-48]
    subsd xmm0, [rbp-96]
    movsd [rbp-40], xmm0
    movsd xmm0, [rbp-40]
    leave
    ret
          
Current calculator valuesUpdates when you change an input above.
              
            
MATLAB
            function result = definite_linear_integral(a, b, x1, x2)
    result = ((((a * (x2 * x2)) / 2.0) + (b * x2)) - (((a * (x1 * x1)) / 2.0) + (b * x1)));
end
          
Current calculator valuesUpdates when you change an input above.
              
            
Wolfram Language
            ClearAll[mwCalculate];
mwCalculate[a_, b_, x1_, x2_] := ((((a * (x2 * x2)) / 2.0) + (b * x2)) - (((a * (x1 * x1)) / 2.0) + (b * x1)));
          
Current calculator valuesUpdates when you change an input above.
              
            

Continue in mathematical software

The downloaded file includes your current inputs and first calculated result. It is created locally.

Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.

Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Calculus Volume 1

Read OpenStax Calculus: Derivatives and integration
Cite this book
APA 7
Strang, G., & Herman, E. (2016). Calculus volume 1. OpenStax. https://openstax.org/books/calculus-volume-1/pages/1-introduction
MLA 9
Strang, Gilbert, and Edwin Herman. Calculus Volume 1. OpenStax, 2016, https://openstax.org/books/calculus-volume-1/pages/1-introduction.
Chicago author-date
Strang, Gilbert, and Edwin Herman. 2016. Calculus Volume 1. Houston, TX: OpenStax. https://openstax.org/books/calculus-volume-1/pages/1-introduction.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Definite Linear Integral Calculator. MW SysArc Tools. https://math.mwsysarc.com/calculus/definite-linear-integral

MLA 9

MW SysArc. “Definite Linear Integral Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/calculus/definite-linear-integral. Accessed 31 Aug. 2026.

Chicago 17

MW SysArc. “Definite Linear Integral Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/calculus/definite-linear-integral.

Harvard

MW SysArc (2026) ‘Definite Linear Integral Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/calculus/definite-linear-integral (Accessed: 31 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_definite_linear_integral_2026,
  author = {{MW SysArc}},
  title = {Definite Linear Integral Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://math.mwsysarc.com/calculus/definite-linear-integral},
  note = {Published July 21, 2026; accessed August 31, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Definite Linear Integral Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-31
UR  - https://math.mwsysarc.com/calculus/definite-linear-integral
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Definite linear integral do?

Integrate mx+b over a finite interval.

How does the Definite linear integral work?

The calculator applies ∫(mx+b)dx=[mx²/2+bx]. The definite integral accumulates signed area under the line.

What can I learn from the Definite linear integral?

It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.

Last reviewed . Calculations tested .

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