# Strange AttributeError

In:

```
bool(-1/2*csc(3/8*pi + x)^2/cot(3/8*pi + x) + 1/cos(1/4*pi + 2*x) == 0)
```

Out:

```
AttributeError: 'sage.rings.complex_interval.ComplexIntervalFieldElement' object has no attribute 'sin'
```

?

Thanks for reporting! This is a bug. Interestingly, this unrelated patch fixes the issue: http://trac.sagemath.org/ticket/15071