Maintenance script: Initial automated import

2016-02-24T18:32:02Z

Initial automated import

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{{Template:TI-BASIC:Command
|picture=TANINVERSE.GIF
|summary=Returns the inverse tangent (also called arctangent)
|syntax=tanֿ¹(''number'')
|location=Press:
# [2nd]
# [tanֿ¹]
|compatibility=TI-83/84/+/SE
|size=1 byte
}}

tanֿ¹( returns the [http://mathworld.wolfram.com/InverseTangent.html arctangent] of its argument. It is the inverse of [[TI-BASIC:Tan|Tan(]], which means that tanֿ¹(n) produces an angle θ such that tan(θ)=n.

Like tan(, the result of tanֿ¹( depends on whether the calculator is in [[TI-BASIC:Radian_Mode|Radian]] or [[TI-BASIC:Degree_Mode|Degree]] mode. However, unlike tangent, the result is in degrees or radians, not the argument. A full rotation around a circle is 2π radians, which is equal to 360°. The conversion of θ=tanֿ¹(n) from radians to degrees is θ*180/π and from degrees to radians is θ*π/180. The tanֿ¹( command also works on a list.

tanֿ¹( will always return a value between -π/2 and π/2 (or -90° and 90°).

In radians:

:tanֿ¹(1)
.7853981634

In degrees:

:tanֿ¹(1)
45

= Optimization =

Expressions of the form tanֿ¹(''y''/''x'') are usually better recast as R►Pθ(''x'',''y''); the latter will not fail even if ''x'' should happen to be equal to zero.

= Error Conditions =

* '''[[TI-BASIC:Errors#datatype|ERR:DATA TYPE]]''' is thrown if you input a complex value or a matrix.

= Related Commands =

* [[TI-BASIC:Sin|Sin(]]
* [[TI-BASIC:Arcsin|sinֿ¹(]]
* [[TI-BASIC:Cos|Cos(]]
* [[TI-BASIC:Arccos|cosֿ¹(]]
* [[TI-BASIC:Tan|Tan(]]
* [[TI-BASIC:R_Ptheta|R►Pθ(]][[Category:TI-BASIC]]
[[Category:TIBD]]

TI-BASIC:Arctan - Revision history

Maintenance script: Initial automated import