Ask Your Question

Sage cannot simplify arccos, but can simplify arcsin?

asked 2013-04-20 18:07:12 +0100

sgia gravatar image

I am using Sage 5.7. It can simplify expressions involving arcsin, but not arccos, why?


assume(x > 0)
assume(x < pi/2)

output: arccos(cos(x))


output: x
edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted

answered 2013-04-20 23:01:20 +0100

kcrisman gravatar image

This is in fact just about Maxima's simplification.

sage: F = asin(sin(x))
sage: F.simplify() # sends to Maxima, nothing else
sage: G = acos(cos(x))
sage: G.simplify()

This Maxima help thread suggests that, as of a couple years ago, this was known but not resolved. I've opened Maxima bug 2570 for this, though I wouldn't expect immediate response as it may be something somewhat deep in the code that isn't easy to unravel - simplification routines can be notorious for this, I guess.

edit flag offensive delete link more


This has now been fixed upstream, and I've opened [Trac 14637]( to add a confirming doctest.

kcrisman gravatar imagekcrisman ( 2013-05-24 09:22:04 +0100 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools


Asked: 2013-04-20 18:07:12 +0100

Seen: 798 times

Last updated: Apr 20 '13