Question

Представьте в виде многочлена: 1) (-c+d)(c+d); 2) (-a+b)(b-a); 3) (-x-y)(x-y); 4) (a+-b); 5) (x-y)(y-x); --b).

Answer 1

1)(-c+d)(c+d)=-(c-d)(c+d)=-(c^2-d^2)=-c^2+d^2
2)(-a+b)(b-a)=(b-a)(b-a)=(b-a)^2=b^2-2ab+a^2=a^2-2ab+b^2
3)(-x-y)(x-y)=-(x+y)(x-y)=-(x^2-y^2)=-x^2+y^2
4)(a+b)(-a-b)=-(a+b)(a+b)=-(a+b)^2=-(a^2+2ab+b^2)=-a^2-2ab-b^2
5)(x-y)(y-x)=-(x-y)(x-y)=-(x-y)^2=-(x^2-2xy+y^2)=-x^2+2xy-y^2
6)(-a-b)(-a-b)=-(a+b)*(-(a+b))=(a+b)^2=a^2+2ab+b^2

Answer 2

1) =-с^2-cd+cd+d^2=-c^2+d^2
2) =-ab+a^2+b^2-ab=a^2-2ab+b^2=(a-b)^2
3) =-x^2+xy-xy+y^2=y^2-x^2
4) =-a^2-ab-ab-b^2=a^2-2ab-b^2
5) =xy-x^2-y^2+xy=-x^2+2xy-y^2=x^2-2xy+y^2=(x-y)^2
6) =a^2+ab+ab+b^2=a*2+2ab+b^2=(a+b)^2