Question

factorise x³+3x²+6x+18

Answer 1

x³ + 3x² + 6x + 18

=> x²( x + 3 ) + 6( x + 3 )

=> ( x + 3 ) ( x² + 6 )

Answer 2

We can factorize it by factor theroem .
First see the value of x which make this polynomial value 0.
i.e p(x)=0
so if x= -3
Then p(-3)=0
therefore its factors will be

X=-3
x+3=0
on dividing p(x) by x+3 we get
${x}^2 + 6$ which is also factor of p(x)