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Is this a bug when multiplying lists?
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In the Algebra View:
a = {x+2, x+3, x+4}
b = {5, 10, 15}
a*b
{x + 2*5, x+3*10, x+4*15}
Why does GeoGebra seem to think that the product of x+2 and 5 is x + 10? How can I instruct GeoGebra that the output should be
{5x + 10, 10x + 30, 15x + 60} ?
The correct result is given in the CAS view  so why not in the Algebra View?
Alasdair
 GeoGebra
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You can check it's right with Polynomial(Element(l1,2)) (it's missing brackets when displayed, that's all).
Workaround
or you might like
Or if you don't want to use Sequence and Element, using Zip is nice and short:
or
if you want it already expanded.
Still a bit weird though that the the list multiplication doesn't work. The elements of the first list seem to be interpreted differently then.
Many thanks. I know I can "force" Geogebra to give me the correct answer by creating a sequence that multiples each pair of elements from the initial sequences, but the thing is, I shouldn't have to. Geogebra has the functionality of multiplying two lists directly  so it should work on symbolic lists as well; that is, brackets should be provided in its internal algorithm.
A list multiplication that acts in the way of my initial example is clearly wrong.
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