Let other roots be a and b.

Now, a+b+1 = 2 which gives  a+b = 1

and a.b.1 = -1 which gives ab = -1

putting a = 1 - b from the first equation in the second, we get

(1-b)b = -1

Solving the above equation, we get b = (1+\root(5))/2 and b = (1-\root(5))/2

hence, the other two roots are (1+\root(5))/2 and (1-\root(5))/2.

Hope this helps.