CBSE Class 9 Answered

i suppose you want to know the factorisation of the given expression..

in such expr.s where the degree (highest power of the variable) is more than 2,

 we take the factors of the term which is free of the variable.. in this case 2.

take all factors of 2, they are +,-1,+,-2

call the given poly. as p(x)

 check if p(1) is zero.

if yes, x-1 is a factor of the poly.

here p(1) is  zero.

so, divide given poly by (x-1) , we get the quotient (x*x)-x-2

this is a quadratic, it can be easily factorised as (x-2)(x+1)

so,

 finally the given poly can be written as

=(x-1)(x+1)(x-2)