Difference between revisions of "NSolve Command"
From GeoGebra Manual
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{{command|geogebra}} | {{command|geogebra}} | ||
;NSolve[ <Equation> ] | ;NSolve[ <Equation> ] | ||
| − | : | + | :Attempts (numerically) to find a solution for the equation for the main variable. |
:{{example|1=<div><code><nowiki>NSolve[cos(x) = x]</nowiki></code> yields ''{x = 0.7390851332151606}''.</div>}} | :{{example|1=<div><code><nowiki>NSolve[cos(x) = x]</nowiki></code> yields ''{x = 0.7390851332151606}''.</div>}} | ||
;NSolve[ <Equation>, <Variable> ] | ;NSolve[ <Equation>, <Variable> ] | ||
| − | : | + | :Attempts (numerically) to find a solution of the equation for the given unknown variable. |
:{{example|1=<div><code><nowiki>NSolve[a^4 + 34a^3 = 34, a]</nowiki></code> yields '' {a = -34.00086498588374, a = 0.9904738885574178}''.</div>}} | :{{example|1=<div><code><nowiki>NSolve[a^4 + 34a^3 = 34, a]</nowiki></code> yields '' {a = -34.00086498588374, a = 0.9904738885574178}''.</div>}} | ||
| − | |||
;NSolve[ <List of Equations>, <List of Variables> ] | ;NSolve[ <List of Equations>, <List of Variables> ] | ||
| − | : | + | :Attempts (numerically) to find a solution of the set of equations for the given set of unknown variables. |
:{{example|1=<div><code><nowiki>NSolve[{π / x = cos(x - 2y), 2 y - π = sin(x)}, {x = 3, y = 1.5}]</nowiki></code> yields ''{x = 3.141592651686591, y = 1.570796327746508}''.</div>}} | :{{example|1=<div><code><nowiki>NSolve[{π / x = cos(x - 2y), 2 y - π = sin(x)}, {x = 3, y = 1.5}]</nowiki></code> yields ''{x = 3.141592651686591, y = 1.570796327746508}''.</div>}} | ||
| − | |||
{{note| 1=<div> | {{note| 1=<div> | ||
| + | * If you don't give a starting point like ''a=3'' or ''{x = 3, y = 1.5}'' the numerical algorithm may find it hard to find a solution (and giving a starting point doesn't guarantee that a solution will be found) | ||
* The number of decimals depends on the choosen in [[Options Menu#Rounding|global rounding]]. | * The number of decimals depends on the choosen in [[Options Menu#Rounding|global rounding]]. | ||
* π is obtaind by pressing {{KeyCode|Alt + p}}. | * π is obtaind by pressing {{KeyCode|Alt + p}}. | ||
* See also [[Solve Command]] and [[NSolutions Command]]. | * See also [[Solve Command]] and [[NSolutions Command]]. | ||
</div>}} | </div>}} | ||
Revision as of 19:51, 13 May 2013
- NSolve[ <Equation> ]
- Attempts (numerically) to find a solution for the equation for the main variable.
- Example:
NSolve[cos(x) = x]yields {x = 0.7390851332151606}.
- NSolve[ <Equation>, <Variable> ]
- Attempts (numerically) to find a solution of the equation for the given unknown variable.
- Example:
NSolve[a^4 + 34a^3 = 34, a]yields {a = -34.00086498588374, a = 0.9904738885574178}.
- NSolve[ <List of Equations>, <List of Variables> ]
- Attempts (numerically) to find a solution of the set of equations for the given set of unknown variables.
- Example:
NSolve[{π / x = cos(x - 2y), 2 y - π = sin(x)}, {x = 3, y = 1.5}]yields {x = 3.141592651686591, y = 1.570796327746508}.
Note:
- If you don't give a starting point like a=3 or {x = 3, y = 1.5} the numerical algorithm may find it hard to find a solution (and giving a starting point doesn't guarantee that a solution will be found)
- The number of decimals depends on the choosen in global rounding.
- π is obtaind by pressing Alt + p.
- See also Solve Command and NSolutions Command.
