Question

17. Factorise : (x2 – 3x) (x2 – 3x - 1) – 20.​

Answer 1

(x2 -√3x)(x2-3x-1)-20

=let, (x2-√3x)=a --------(1)

=a(a-1)-20

=a2-a-20

=a(a-5)+4(a-5)

=(a-5)(a-4)

=(x2-3x-5)(x2-3x+4).

I hope this helps you :-)