Difference between revisions of "Intersect Command"
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Noel Lambert (talk | contribs) (typo) |
(removed unnecessary elements in the examples - CAS: yields the list of inters. pts) |
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:Yields the intersection points of two objects. | :Yields the intersection points of two objects. | ||
:{{example|1=<div> | :{{example|1=<div> | ||
− | :* Let <code><nowiki>a: -3x + 7y = -10</nowiki></code> be a line | + | :* Let <code><nowiki>a: -3x + 7y = -10</nowiki></code> be a line and <code><nowiki>c: x^2 + 2y^2 = 8</nowiki></code> be an ellipse. <code><nowiki>Intersect[a, c]</nowiki></code> yields the intersection points ''E'' = (-1.02, -1,87) and ''F'' = (2.81, -0.22) of the line and the ellipse. |
− | :* <code><nowiki>Intersect[y = x + 3, Curve[t, 2t, t, 0, 10]]</nowiki></code> yields ''A(3,6) | + | :* <code><nowiki>Intersect[y = x + 3, Curve[t, 2t, t, 0, 10]]</nowiki></code> yields ''A''=(3,6). |
− | :*<code><nowiki>Intersect[Curve[2s, 5s, s,-10, 10 ], Curve[t,2t,t,-10,10]]</nowiki></code> yields ''A(0,0) | + | :*<code><nowiki>Intersect[Curve[2s, 5s, s,-10, 10 ], Curve[t, 2t, t, -10, 10]]</nowiki></code> yields ''A''=(0,0). </div>}} |
;Intersect[ <Object>, <Object>, <Index of Intersection Point> ] | ;Intersect[ <Object>, <Object>, <Index of Intersection Point> ] | ||
:Yields the n<sup>th</sup> intersection point of two objects. | :Yields the n<sup>th</sup> intersection point of two objects. | ||
− | :{{example|1=<div>Let <code><nowiki>a(x) = x^3 + x^2 - x</nowiki></code> be a function and <code><nowiki>b: -3x + 5y = 4</nowiki></code> be a line | + | :{{example|1=<div>Let <code><nowiki>a(x) = x^3 + x^2 - x</nowiki></code> be a function and <code><nowiki>b: -3x + 5y = 4</nowiki></code> be a line. <code><nowiki>Intersect[a, b, 2]</nowiki></code> yields the intersection point ''C'' = (-0.43, 0.54) of the function and the line.</div>}} |
;Intersect[ <Object>, <Object>, <Initial Point> ] | ;Intersect[ <Object>, <Object>, <Initial Point> ] | ||
:Yields an intersection point of two objects by using a (numerical) iterative method with initial point. | :Yields an intersection point of two objects by using a (numerical) iterative method with initial point. | ||
− | :{{example|1=<div>Let <code><nowiki>a(x) = x^3 + x^2 - x</nowiki></code> be a function, <code><nowiki>b: -3x + 5y = 4</nowiki></code> be a line | + | :{{example|1=<div>Let <code><nowiki>a(x) = x^3 + x^2 - x</nowiki></code> be a function, <code><nowiki>b: -3x + 5y = 4</nowiki></code> be a line, and ''C'' = (0, 0.8) be the initial point. <code><nowiki>Intersect[a, b, C]</nowiki></code> yields the intersection point ''D'' = (-0.43, 0.54) of the function and the line by using a (numerical) iterative method.</div>}} |
;Intersect[ <Function>, <Function>, <Start x-Value>, <End x-Value> ] | ;Intersect[ <Function>, <Function>, <Start x-Value>, <End x-Value> ] | ||
:Yields the intersection points numerically for the two functions in the given interval. | :Yields the intersection points numerically for the two functions in the given interval. | ||
− | :{{example|1=<div>Let <code><nowiki>f(x) = x^3 + x^2 - x</nowiki></code> and <code><nowiki>g(x) = 4 / 5 + 3 / 5 x</nowiki></code> be two functions. <code><nowiki>Intersect[ f, g, -1, 2 ]</nowiki></code> yields | + | :{{example|1=<div>Let <code><nowiki>f(x) = x^3 + x^2 - x</nowiki></code> and <code><nowiki>g(x) = 4 / 5 + 3 / 5 x</nowiki></code> be two functions. <code><nowiki>Intersect[ f, g, -1, 2 ]</nowiki></code> yields the intersection points ''A'' = (-0.43, 0.54) and ''B'' = (1.1, 1.46) of the two functions in the interval [ -1, 2 ].</div>}} |
;Intersect[ <Curve 1>, <Curve 2>, <Parameter 1>, <Parameter 2> ] | ;Intersect[ <Curve 1>, <Curve 2>, <Parameter 1>, <Parameter 2> ] | ||
:Finds one intersection point using an iterative method starting at the given parameters. | :Finds one intersection point using an iterative method starting at the given parameters. | ||
Line 22: | Line 22: | ||
==CAS Syntax== | ==CAS Syntax== | ||
;Intersect[ <Function>, <Function> ] | ;Intersect[ <Function>, <Function> ] | ||
− | :Yields the intersection points of two objects. | + | :Yields a list containing the intersection points of two objects. |
− | :{{example|1=<div>Let <code><nowiki>f(x):= x^3 + x^2 - x</nowiki></code> and <code><nowiki>g(x):= x</nowiki></code> be two functions. <code><nowiki>Intersect[ f(x), g(x) ]</nowiki></code> yields the intersection points ''{(1, 1), (0, 0), (-2, -2)}'' of the two functions.</div>}} | + | :{{example|1=<div>Let <code><nowiki>f(x):= x^3 + x^2 - x</nowiki></code> and <code><nowiki>g(x):= x</nowiki></code> be two functions. <code><nowiki>Intersect[ f(x), g(x) ]</nowiki></code> yields the intersection points list: ''{(1, 1), (0, 0), (-2, -2)}'' of the two functions.</div>}} |
{{Note| See also [[Image:Tool Intersect Two Objects.gif]] [[Intersect Tool|Intersect]] tool.}} | {{Note| See also [[Image:Tool Intersect Two Objects.gif]] [[Intersect Tool|Intersect]] tool.}} |
Revision as of 12:48, 11 February 2014
- Intersect[ <Object>, <Object> ]
- Yields the intersection points of two objects.
- Example:
- Let
a: -3x + 7y = -10
be a line andc: x^2 + 2y^2 = 8
be an ellipse.Intersect[a, c]
yields the intersection points E = (-1.02, -1,87) and F = (2.81, -0.22) of the line and the ellipse. Intersect[y = x + 3, Curve[t, 2t, t, 0, 10]]
yields A=(3,6).Intersect[Curve[2s, 5s, s,-10, 10 ], Curve[t, 2t, t, -10, 10]]
yields A=(0,0).
- Let
- Intersect[ <Object>, <Object>, <Index of Intersection Point> ]
- Yields the nth intersection point of two objects.
- Example:Let
a(x) = x^3 + x^2 - x
be a function andb: -3x + 5y = 4
be a line.Intersect[a, b, 2]
yields the intersection point C = (-0.43, 0.54) of the function and the line.
- Intersect[ <Object>, <Object>, <Initial Point> ]
- Yields an intersection point of two objects by using a (numerical) iterative method with initial point.
- Example:Let
a(x) = x^3 + x^2 - x
be a function,b: -3x + 5y = 4
be a line, and C = (0, 0.8) be the initial point.Intersect[a, b, C]
yields the intersection point D = (-0.43, 0.54) of the function and the line by using a (numerical) iterative method.
- Intersect[ <Function>, <Function>, <Start x-Value>, <End x-Value> ]
- Yields the intersection points numerically for the two functions in the given interval.
- Example:Let
f(x) = x^3 + x^2 - x
andg(x) = 4 / 5 + 3 / 5 x
be two functions.Intersect[ f, g, -1, 2 ]
yields the intersection points A = (-0.43, 0.54) and B = (1.1, 1.46) of the two functions in the interval [ -1, 2 ].
- Intersect[ <Curve 1>, <Curve 2>, <Parameter 1>, <Parameter 2> ]
- Finds one intersection point using an iterative method starting at the given parameters.
- Example:Let
a = Curve[cos(t), sin(t), t, 0, π]
andb = Curve[cos(t) + 1, sin(t), t, 0, π]
.Intersect[a, b, 0, 2]
yields the intersection point A = (0.5, 0.87).
CAS Syntax
- Intersect[ <Function>, <Function> ]
- Yields a list containing the intersection points of two objects.
- Example:Let
f(x):= x^3 + x^2 - x
andg(x):= x
be two functions.Intersect[ f(x), g(x) ]
yields the intersection points list: {(1, 1), (0, 0), (-2, -2)} of the two functions.
Note: See also Intersect tool.
Following text is about a feature that is supported only in GeoGebra 5.0.
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