Hello, I am beginner with Maple 18, started recently, so I have some silly questions. I'm training the algebra study in Maple and got a list of exercises on the Internet, where they were asked to Prove it {5, 15, 25, 45, 55, 65} is a group with mod multiplication operation 90. If so, calculate the identity element and inverse of any element.

group.mw

Exercise: Find all the elements of order 2 in D30 .

I set the D30 group , but I do not know how to calculate and list elements of order 2 . I thought of calculating the order of all the elements ( With PermOrder () command , perhaps) , and then use the select command to select those with order of 2. But the big problem is to calculate the order of elements.

I know only calculate the order of the group. Could anyone help me ?

I'm trying to create a routine to perform the test of rational roots , but I'm having some problems. Below is the routine I created :

But the program is only printing " aux = -24 " . I don't know what it can be .

I need to modify my code , but I don't know where. Can someone help me? Thank you!