Given:
The function is:

It is given that -1 is a zero of the given function.
To find:
The other zeroes of the given function.
Solution:
If c is a zero of a polynomial P(x), then (x-c) is a factor of the polynomial.
It is given that -1 is a zero of the given function. So,
is a factor of the given function.
We have,

Split the middle terms in such a way so that we get (x+1) as a factor.



Again splitting the middle term, we get



For zeroes,
.

and
and 
and
and 
Therefore, the other two zeroes of the given function are
and
.