Question

先化简，再求值：[(x-y)的平方+(x+y)(x-y)]÷2x,其中x=y+5

Answer 1

[(x-y)^2 +(x+y)(x-y)]÷2x
=[x^2-2xy+y^2+x^2-y^2]÷2x
=2x^2 -2xy /2x
=x-y
x=y+5
x-y=5

所以 [(x-y)^2 +(x+y)(x-y)]÷2x =5

追问

已知被除式是2x的三次方+6x的平方-2，商式是x，余数是-2，求除式.

追答

除式=被除式*商式+余数
=(2x^3 +6x^2 -2)x -2

Answer 2

=[(x-y)*(x-y)+(x+y)*(x-y)]/2x
==(x-y)*(x-y+x+y)/2x
=x-y
然后=5

追问

已知被除式是2x的三次方+6x的平方-2，商式是x，余数是-2，求除式.

Answer 3

【（X-Y）（X-Y）+（X+Y）(X-Y)】/2X=[(X-Y)(X-Y+X+Y)]/2X=(X-Y)2X/2X=X-Y=5

追问

已知被除式是2x的三次方+6x的平方-2，商式是x，余数是-2，求除式.