(X+2)(X+2)- 1 =(X+3)(X+3)-4Y
问题描述:
(X+2)(X+2)- 1 =(X+3)(X+3)-4Y
(X-1)(Y+6)=(X+2)(Y+4)
计算……
(-X-Y)(X-Y)=
(3A-B)(-B-3A)=?
(-XY+1/2)(-1/2-XY)=?
(X+2)(X-2)(X的平方+4)=?
答
1.(X+3)(x+1)=x方+4x+3=x方+6x+9-4y 2x-4y=-6
xy-6+6x-y=xy+8+4x+2y
根据2式 2x-3y=14
y=20 x=37
(-X-Y)(X-Y)= -(x+y)(x-y)=y平方-x平方
(3A-B)(-B-3A)=-(3A+B)(3A-B)=B平方-9A平方
(-XY+1/2)(-1/2-XY)=X平方y平方-1/4
(X+2)(X-2)(X的平方+4)=(X平方-4)(X平方+4)=X四次方-16