Given expression,f(x)=x3+6x2+11x+6
Put, x=−1
f(−1)=−13+6(−1)2+11(−1)+6=0
Again put x=−2
f(−2)=(−2)3+6(−2)2+11(−2)+6=0
Again put x= -3 we get,
f(−3)=(−3)3+6(−3)2+11(−3)+6=0
Hence,
x3+6x2+11x+6=(x−1)(x−2)(x−1)