# (abs(sin(x))^2).simplify_full()

I think (abs(sin(x))^2).simplify_full() should render sin(x)^2. This is not the case in sage 5.6 even with the assumption assume(x, 'real'). Is this a [known] bug?

(abs(sin(x))^2).simplify_full()

0

I think that Maxima (which handles simplification and assumptions) is correct insofar that

```
sage: assume(x,"real")
sage: (abs(sin(x))^2).simplify_full()
abs(sin(x))^2
sage: (abs(x)^2).simplify_full()
x^2
```

because it can't assume `sin(x)`

to be real. But trying that gives an error,
so, even if Maxima doesn't know by itself that `sin(x)`

is real, there should
be a means to specify it.

Asked: **
2013-01-29 03:07:09 -0500
**

Seen: **137 times**

Last updated: **Jan 26 '15**

possible bug involving absolute value of sin function and assume

simplify_full - is the mistake in the documentation or the source code?

QQ.extension() with embedding: incorrect modulus

equation not simplifying and substituting properly

Is there a way to simplify_full and trig_reduce a matrix?

Simplify trig expressions with the double angle formula

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.

Here, using Ubuntu 12.04, it consistently yields abs(sin(x))^2. Please note that the similar input abs(sin(x)^2).simplify_full() produces the right answer. Version 5.5 does not have this problem.