.
0. Let the original equation be
= 0. (1)
1. After the 1-st student incorrectly copied the coefficient at
, the equation took the form
= 0. (2)
Since its roots are 2 and 3, we have this decomposition
= d*(x-2)*(x-3), or
=
.
So, the original equation (1) has the two lowest degree terms -5dx + 6d:
=
(3)
with some unknown coefficients "a" and "d".
2. After the 2-nd student incorrectly copied the constant term, the equation took the form
= 0. (4)
Since its roots are 4 and 6, we have this decomposition
= a*(x-4)*(x-6), or
=
.
It implies -5d = -10a, which in turn implies d = 2a.
Now from (3) we conclude that the original equation (polynomial) is/was
=
.
Its roots are the same as for equation
= 0.
And they are
=
=
.
Answer. The roots of the original equation are
=
and
=
.