简单的因式分解填空题和计算题

选择因式分解方法的原则是:先提出____.在没有公因式的情况下,二项式用_____公式,三项式用十字____法,三项以上用_______法.
2.31X5.41^2-2.31X4.59^2=______. 73^2-2X73X23+23^2=______
以下计算要有过程
X(Y-3)+X^2(3-y) 5A-5B+A^2-AB X^6-(X^4)(Y^2)+3(X^2)(Y^3)-3(X^4)Y 25X^2+25X+35Y-49Y^2
(X^2+5X-1)(X^2+5X+5)-7

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码字好辛苦啊

公因式

平方并橘尘差

相乘

分组分伍庆解

18.942

2500

X(Y-3)+X^2(3-y)＝X(Y-3)-X^2(Y-3)=X(Y-3)(1-X)

5A-5B+A^2-AB=(5A-5B)+(A^2-AB)=5(A-B)+A(A-B)=(5+A)(A-B)

X^6-(X^4)(Y^2)+3(X^2)(Y^3)-3(X^4)Y=(X^6-X^4Y^2)+(3X^2Y^3-3X^4Y)=X^4(X^2-Y^2)+3X^2Y(Y^2-X^2)=(X^4-3X^2Y)(X^2-Y^2)=X^2(X^2-3Y)(X+Y)(X-Y)

25X^2+25X+35Y-49Y^2=25X(X+1)+7Y(5-7Y)

令Y=X^2+5X则绝禅
(X^2+5X-1)(X^2+5X+5)-7=(Y-1)(Y+5)-7=Y^2+4Y-12=(Y+6)(Y-2)=(X^2+5X+6)(X^2+5X-2)=(X+2)(X+3)(X^2+5X-2)

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