Question

equation done.

Answer 1

To work this out, substitute x=1 into P(x) to get P(1) and see if it equals 0. If it does, then 1 is a root of P(x).
P.S: I'm assuming you meant "Is x=1 a root of P(x)" and not "r=1".

Answer 2

okay i tried it and it didn't equal to 0?

Answer 3

So, it not a root then

Answer 4

p(1) = 1^3+3* (1^2)-2*2+1=3