Factorise: 9a2+6a+1−36b2
9a2+6a+1−36b2 =(3a)2+2×3a×1+12−(6b)2=(3a+1)2−(6b)2[a2+2ab+b2=(a+b)2]=(3a+1−6b)(3a+1+6b)[a2−b2=(a−b)(a+b)]=(3a−6b+1)(3a+6b+1)
Factorise:
9a2+19a2−2−12a+43a
Factorise: 49a2+84ab+36b2