MathAction #333 asin 1.0 over Complex Float fails

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The first real calculus is right, the second fails.

fricas

(1) -> asin 1.0

$\label{eq1}1.5707963267 \<u> 948966192$

Type: Float

fricas

asin (1.0+0*%i)

$\label{eq2}1.5707963267 \<u> 948966192$

Type: Complex(Float)

The problem is perhaps line 162 of trigcat.spad. There is no test for the ... / sqrt (1-x^2) in asin definition.

asin x == atan(x/sqrt(1-x**2))

patch possible. --Francois Maltey, Fri, 05 Jan 2007 07:57:48 -0600 reply
I propose to remplace in asin x == atan (x/sqrt(1-x**2)) in trigcat.spad line 162 by

asin x == x=1 => 2atan 1 x=-1 => -2atan 1 atan(x/sqrt(1-x**2))

The result seems right...

See #138 --kratt6, Thu, 20 Dec 2007 02:09:52 -0800 reply

Category: Axiom Mathematics => Axiom Library Status: open => duplicate