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1)-(-1/3 X+Y)+(1/6X-Y) (4) -1/2(5mn-2m²+3n²)+(-3/2

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/27 06:18:14
1)-(-1/3 X+Y)+(1/6X-Y) (4) -1/2(5mn-2m²+3n²)+(-3/2mn+2m²+n²/2)
(5)(a³+1/5a²b+3)-1/2(a²b-6)
(2)(2S+1)-3(S²-S+2)
(3) -2(a²b-1/4ab²+1/2a³)-(-2a²b+3ab²)
(6)-3(1/2X³-1/3Y³+2(1/3³-1/2Y³+1/4
1)-(-1/3 X+Y)+(1/6X-Y)
1/3X-Y+1/6X-Y=1/2X-2Y
(2)(2S+1)-3(S²-S+2)
2S+1-3S²+3S-6=3S²+5S-5
(3) -2(a²b-1/4ab²+1/2a³)-(-2a²b+3ab²)
-2a²b+1/2ab²-a³+2a²b-3ab²=-(5/2ab²+a³)
(4) -1/2(5mn-2m²+3n²)+(-3/2mn+2m²+n²/2)
-5/2mn+m²-3/2n²-3/2mn+2m²+n²/2=-4mn+3m²-n²=(3m-n)(m-n)=6mn
(5)(a³+1/5a²b+3)-1/2(a²b-6)
a³+1/5a²b+3-1/2a²b+3=a³-3/10a²b+6
(6)-3(1/2X³-1/3Y³+2(1/3³-1/2Y³+1/4
-3/2X³+Y³-3/2+2/3X³-Y³+1/2=-(5/6X³+1)
再问: 高手啊! 再帮我解一点 我给你加30分 说话算数! 我还以为没人会理我 就算少了分 拜托了!! 二(1)(-1/2)³×(-1/2) (2)-(a+b)^5×(a+b)² (3)(-2a^5)^4 (4)(-1/2X)^4÷(-1/2X) (5)(-a³×b)² (6)b×(-b²(b²)³ (7)(-Y³)²÷Y^6 (8)a^2n +1×a^2n-1 (9)(9X-2Y)(X+Y)
再答: (1)(-1/2)³×(-1/2)=(-1/2)^4=1/16 (2)-(a+b)^5×(a+b)² =-(a+b)^7 (3)(-2a^5)^4=16a^20 (4) (-1/2X)^4÷(-1/2X)=(-1/2X)³ (5)(-a³×b)² =a^6b² (6)b×(-b²(b²)³=b×(-b^(2b^6)=-b^(2b^6+1) (7)(-Y³)²÷Y^6 =Y^6÷Y^6=1 (8)a^2n +1×a^2n-1 =a^2n(1+1/a) (9)(9X-2Y)(X+Y)=9X²+9XY-2XY-2Y²=9X²+7XY-2Y² 就回答这些,不能再追加了。