简便123²-122×124 ﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚ 今天就要

简便123²-122×124 ﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚ 今天就要
简便123²-122×124 ﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚ 今天就要

简便123²-122×124 ﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚ 今天就要
123²-122×124
=123²-(123-1)(123+1)
=123²-(123²-1)
=123²-123²+1
=1
﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚
=（4a²-4a+1）-4（a²-1）
=4a²-4a+1-4a²+4
=-4a+5

123²-122×124=123²-(123+1)×(123-1)=123²-123²+1=1
﹙2a－1﹚²－4﹙a－1﹚﹙a＋1﹚=﹙2a－1﹚²－4a²+4=4a²-4a+1-4a²+4=-4a+5

123^2-122*124
=123^2-(123-1)(123+1)
=123^2-123^2+1
=1
(2a-1)^2-4(a-1)(a+1)
=4a^2-4a+1-4(a^2-1)
=4a^2-4a+1-4a^2+4
=5-4a
(2/3ab^2)*(-2a)^3
=(2/3ab^2)*(-8a^3)
=-2/...

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123^2-122*124
=123^2-(123-1)(123+1)
=123^2-123^2+1
=1
(2a-1)^2-4(a-1)(a+1)
=4a^2-4a+1-4(a^2-1)
=4a^2-4a+1-4a^2+4
=5-4a
(2/3ab^2)*(-2a)^3
=(2/3ab^2)*(-8a^3)
=-2/3*8*a^(1+3)b^2
=-16/3a^4b^2
1+﹙-½﹚^(-2)－﹙3.14－π)
=1+﹙-2﹚^2－﹙3.14－π)
=1+4－3.14+π
=1+4－3.14+π
=π+1.86

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