Trinomial is 3 terms ax^2+bx+c 4 is a perfect square since 2*2 essentially, you need (x+a)^2 (x+1)^2=(x+1)(x+1)=x^2+2x+1 as far as "special patterns" this may imply that you need to find a perfect square trinomial that requires a different factoring process, I'm not sure what that means