(a+2b)(a+3b). (x2+5)(x2+5). (x−9)(x−9). (x−10)(x−11). (x+8)(x+11). (x−8)(x+11). (x2+1)(x−1). x2(3x+1)(3x−1). (1+a−b)(1−a+b). (a+b)(a2−ab+b2+1). (m+n)(m−n)(x+y). (x−y+z)(x−y−z). (z+x−y)(z−x+y). (2a2+3a−1)(2a2−3a+1). (2x−y)(4x2+2xy+y2). x2(x−3y). (x−3y)(x2+3xy+9y2). (x−5)(x+8). (x−2y)(x+5y). (1+4x)(1−4x). a2(a2+3b2)(a2−3b2). x(x+y)(x+2y). x2(x+y)(x+3y). (x−2y2)(x−2y2). (4x2+1)(4x2+1). a2(3a+2c)(3a−2c).