Question

81.21. 1) (a – y)(a + y)(a? + y^); 2) (7x + 1)(7x - 1)(49x2 + 1); 3) (x - 6yº)2 . (x + 6y3)2; 4)(8 + x)(8 - x'). (64+ x);
5) (25x² + y)(5x + y)(5x - y); 6) (81a4+1664)(962 +4a )(4a - 96).

все выставил​

Answer 1

1)0,7*(-0.8)*a^2*a^5*y*y^10=-0,56a^7y^11

2)-0.4a^5*625a^12=-0.4*625*a^5*a^12=-250a^17

3)81*x^28*y^12*1/81*x*y=81*1/81x^28*x*y^12*y=x^29y^13

4)3y^2+3y-4-y^2+2y-7=3y^2-y^2+3y+2y-4-7=2y^2+5y-11

5)2c*c^2+2c*3c=2c^3+6c^2

6)x*x^2+x*2x-x*3+4*x^2+4*2x-4*3=x^3+2x^3-3x+4x^2+8x-12=7x^3+5x-12

7)x*x^2+x*2x-x*3+1*x^2+1*2x-1*3=x^3+2x^2-3x+x^2+2x-3=x^3+3x^2-x-3

8)15:1/5x^2:xy:y+10:1/5x:xy:y=75x+50

Объяснение: