3. a b a a b b SUMA (a + b)2 = a2 + ab + ab + b2 (a + b)2 = a2 + 2ab + b2 b a
4. b b2 b DIFERENCIA (a – b)2 = a2 – [(a – b) b + (a – b)b + b2] (a – b)2 = a2 – [(ab – b2) + (ab – b2) + b2 ] (a – b)2 = a2 – ab + b2 – ab + b2 – b2 (a – b)2 = a2 – 2ab + b2 a a - b ab – b2 a a - b (a – b)2
5. MULTIPLICACIÓN DE BINOMIOS CON UN TÉRMINO COMÚN (x + a) (x + b) = x2 + (a + b)x + ab x a ax x2 x x bx ab b b a x x2 + ax + bx + ab (x + a) (x + b) = (x + a) (x + b) = x2+ (a + b)x + ab