The polynomial p(x) is given: p(x)=x^3+2x^2-5x-6, express p(x) as the product of three linear factors
p(x)=x3+2x2-5x-6
=x(x2+2x-5)-6
=x(x2+2x+1-6)-6 as we know (x+1)2=x2+2x+1,5 can be expressed 1-6
=x[(x+1)2-6]-6
=x(x+1)2-6x-6
=x(x+1)2-6(x+1)
=(x+1)[x(x+1)-6]
=(x+1)(x2+x-6) here, -6 can be expressed as -2*3, and -2+3=1
=(x+1)(x+3)(x-2)
