Формула: (a−b)(a+b)= a²-b² Представьте в виде многочлена произведение: 1) (x-3)(x+3); 2) (8-a)(8+a); 3) (b-5)(b+5); 4) (7+b)(7-b); 5) (y+2)(2-y); 6) (a-4)(4+a); 7) (1+c)(-1+c); 8) (6-a)(-a-6); 9) (-b+1)(b+1); 10) (-x-5)(x-5); 11) (1-4x)(1+4x); 12) (5b-7)(5b+7); 13) (8x+9)(9-8x); 14) (x+\frac{3}{4})(x-\frac{3}{4}); 15) (4y+5b)(4y-5b); 16) (0,5m+7x)(7x-0,5m); 17) (\frac{2}{7}y-0,2z)(0,2z+\frac{2}{7}y); 18) (0,8ab-\frac{1}{3}c)(0,8ab+\frac{1}{3}c); 19) (-0,4mn+1,1xy)××(0,4mn+1,1xy); 20) (\frac{1}{5}pq-\frac{2}{9})(\frac{1}{5}pq-\frac{2}{9})

1) (x-3)(x+3) = x² - 9 2) (8-a)(8+a) = 64 - a² 3) (b-5)(b+5) = b² - 25 4) (7+b)(7-b) = 49 - b² 5) (y+2)(2-y) = 4 - y² 6) (a-4)(4+a) = a² - 16 7) (1+c)(-1+c) = c² - 1 8) (6-a)(-a-6) = (6-a)(-6-a)=(6-a)(-(6+a))=-(36-a^2)= a²-36 9) (-b+1)(b+1) = (1-b)(1+b)=1-b^2 10) (-x-5)(x-5) = (5+x)(5-x)=25-x^2 11) (1-4x)(1+4x) = 1 - 16x² 12) (5b-7)(5b+7) = 25b² - 49 13) (8x+9)(9-8x) = (9+8x)(9-8x)=81-64x^2 14) (x+\frac{3}{4})(x-\frac{3}{4}) = x^2 - \frac{9}{16} 15) (4y+5b)(4y-5b) = 16y² - 25b² 16) (0,5m+7x)(7x-0,5m) = 49x^2 - 0.25m^2 17) (\frac{2}{7}y-0,2z)(0,2z+\frac{2}{7}y)=(\frac{2}{7}y-0.2z)(\frac{2}{7}y+0.2z)=(\frac{2}{7}y)^2-(0.2z)^2=\frac{4}{49}y^2-0.04z^2 18) (0,8ab-\frac{1}{3}c)(0,8ab+\frac{1}{3}c) = 0.64a^2b^2 - \frac{1}{9}c^2 19) (-0,4mn+1,1xy)(0,4mn+1,1xy) = (1.1xy-0.4mn)(1.1xy+0.4mn)=(1.1xy)^2 - (0.4mn)^2= 1.21x^2y^2 - 0.16m^2n^2 20) (\frac{1}{5}pq-\frac{2}{9})(\frac{1}{5}pq-\frac{2}{9}) = (\frac{1}{5}pq-\frac{2}{9})^2 = \frac{1}{25}p^2q^2 - \frac{4}{45}pq + \frac{4}{81}