Correct, but convoluted answer?

asked 2014-08-20 04:34:05 +0100

This absolute value inequality $$5\left| 2x-3\right| + 3 < 23$$ is satisfied when $$x \in \left( - \frac{1}{2}, \ \frac{7}{2} \right)$$. When I ask Sage to solve it, with this command

solve(5*abs(2*x-3)+3<23, x)

I get the same solution, but in a very convoluted way, as follows:

[[(-1/2) < x, x < (3/2)], [x == (3/2)], [(3/2) < x, x < (7/2)]]

Does this seem strange to anyone else?

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Perhaps, but this is how Maxima returns the answer, essentially, in such situations - I believe the documentation has several examples like this.

kcrisman gravatar imagekcrisman ( 2014-08-20 14:36:53 +0100 )edit

On the other hand, Sage could try to simplify intervals returned by Maxima. So, an enhancement ticket is needed.

rws gravatar imagerws ( 2014-08-20 15:06:51 +0100 )edit

Okay, that seems fine! Though it probably won't be as high-priority :-) Or one could open a Maxima ticket asking for this, though the same comment applies.

kcrisman gravatar imagekcrisman ( 2014-08-20 15:38:00 +0100 )edit