亚洲激情+欧美激情,无码任你躁久久久久久,我的极品美女老婆,性欧美牲交在线视频,亚洲av高清在线一区二区三区

電子課本網(wǎng) 第54頁

第54頁

信息發(fā)布者:
?$(a+b)^2$?
?$(a-b)^2$?
和或差
平方差公式
完全平方公式
D
A
A
?$(x+1)^2$?
?$(m+n-3)^2$?
±?$\frac {2}{3}$?xy
±?$\frac {1}{3}$?
?$\frac {1}{4}$?
x+?$\frac {1}{2}$?
?$10000$?
?$10 $?
解:原式?$=(2 x)^2-2(2 x)(3 y)+(3 y)^2 $?
?$=(2 x-3 y)^2$?
解:原式?$= (\frac {x}{2})^2+2(\frac {x}{2}) y+y^2 $?
?$= (\frac {x}{2}+y)^2$?
解:原式?$=(\frac {\sqrt{2}}{2}m)^2-2×(\frac {\sqrt{2}}{2}m)(\frac {\sqrt{3}}{2}n)$?
?$+(\frac {\sqrt{2}}{2}n)^2$?
?$=(\frac {\sqrt{2}}{2}m-\frac {\sqrt{2}}{2}n)^2$?
?$=[\frac {\sqrt{2}}{2}(m-n)]^2$?
?$=\frac {1}{2}(m-n)^2$?
?$\begin{aligned}解:原式=&-(x^2-6xy+9y^2)\\=&-[x^2-2x(3y)+(3y)^2]\\=&-(x-3y)^2\end{aligned}$?
解:原式?$=3(x^2+2 x y+y^2) $?
?$=3(x+y)^2 $?
解:原式?$=x(x^2-2 x+1) $?
?$=x(x-1)^2 $?