These two lines should be written in a manner similar to the preceding:

```
if self.args[0].is_negative:
    return (self.args[0] + 1).is_positive
```

These lines will, however, likely never return anything fruitful since any negative NUMBER args are converted to positive

```
>>> asin(-Rational(1,7))
-asin(1/7)
>>> var('n', negative=1)
n
>>> asin(n)
asin(n)
```

And if the argument is symbolic, the old assumptions won't be able to figure out that the arg + 1 is positive. So the only way to test this is to use an unevaluated expression: `assert asin(Rational(-1, 7), evaluate=False).is_positive is False`