# Solving equation f(x) = 0

## Case 1: Solve 2x-4 = 0 for x in [0, 10]

// JAVA: import org.mariuszgromada.math.mxparser.*;
// ...
Expression e = new Expression("solve( 2*x - 4, x, 0, 10 )");
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate() );

[mXparser-v.5.2.1] Res: solve( 2*x - 4, x, 0, 10 ) = 2.0


## Case 2: Solve cos(x) = 0 for x in [0, pi]

// JAVA: import org.mariuszgromada.math.mxparser.*;
// ...
Expression e = new Expression("solve( cos(x), x, 0, pi )");
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate() );

[mXparser-v.5.2.1] Res: solve( cos(x), x, 0, pi ) = 1.57079633


## Case 3: Solve cos(x) = 0 for x in [pi, pi] (root not bracketed)

// JAVA: import org.mariuszgromada.math.mxparser.*;
// ...
Expression e = new Expression("solve( cos(x), x, -pi, pi )");
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate() );

[mXparser-v.5.2.1] Res: solve( cos(x), x, -pi, pi ) = -1.57079633


## Case 4: Solve x-y = 0 for x in [0, 10] and y = 4

// JAVA: import org.mariuszgromada.math.mxparser.*;
// ...
Argument y = new Argument("y = 4");
Expression e = new Expression("solve( x-y, x, 0, 10 )", y);
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate() );

[mXparser-v.5.2.1] Res: solve( x-y, x, 0, 10 ) = 4.0


## Case 5: Solve sin'(x) = 0 for x in [0, pi]

// JAVA: import org.mariuszgromada.math.mxparser.*;
// ...
Argument x = new Argument("x");
Expression e = new Expression("solve( der( sin(x), x ), x, 0, pi )", x);
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate() );

[mXparser-v.5.2.1] Res: solve( der( sin(x), x ), x, 0, pi ) = 1.57079633

###### Nuget – Package Manager

Install-Package MathParser.org-mXparser -Version 6.0.0

Nuget – .NET CLI

dotnet add package MathParser.org-mXparser --version 6.0.0

Nuget – Package Reference

<PackageReference Include="MathParser.org-mXparser" Version="6.0.0"/>

###### Maven – Dependency

<dependency><groupid>org.mariuszgromada.math</groupid><artifactid>MathParser.org-mXparser</artifactid><version>6.0.0</version></dependency>

implementation 'org.mariuszgromada.math:MathParser.org-mXparser:6.0.0'

implementation("org.mariuszgromada.math:MathParser.org-mXparser:6.0.0")

###### GitHub

git clone https://github.com/mariuszgromada/MathParser.org-mXparser