先化简,再求值:(2a b)2-a(4a 3b)
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/23 17:50:49
(1)4ab+8-2b2-9ab-6=-2b2-5ab+2(2)原式=3x2y-2x2y+6xy-3x2y+xy=-2x2y+7xy,当x=-1,y=-2时,原式=-2×(-1)2(-2)+7×(-1
2a√(3ab³)-b/6*√(27a³b³)+2ab√(3ab/4)=2ab√(3ab)-a²b/2*√(3ab)+ab√(3ab)=3ab√(3ab)-a&
a,b满足|a+√3|+√b-2{根号(b-2)}=0a+√3=0b-2=0a=-√3b=22(a平方b-ab)-3(a平方b-三分之二ab)=2a^2b-2ab-3a^2b+2ab=-a^2b=-(
∵a2+ab-2b2=0∴(a+2b)(a-b)=0∴a=-2b或者a=b原式=(a²-b²-a²-b²)/ab=-2b²/ab=-2b/a当a=-2
解[(a+b)²/a-[a-(2ab-b²)/a]=(a+b)²/a-[(a²-2ab+b²)/a]=(a²+2ab+b²)/a-
原式=(a−2a(a+2)-a−1(a+2)2)•a+2a−4 =a2−4−a2+aa(a+2)2•a+2a−4 =1a2+2a.由a2+2a-1=0,得a2+2a=1,∴原式=1
当a=1,b=-1时3ab-2{a²-ab]-[a²-ab]=3ab-(a²-ab)=4ab-a²=4×1×(-1)-(1)²=-4-1=-5
(a/ab-b^2-b/a^2-ab)/(1+a^2+b^2/2ab),其中a=-2,b=1=[a/b(a-b)-b/a(a-b)]/[(2ab+a²+b²)/2ab]=[(a
补充:[(a)-(《2ab-b^2》]/a通分得(a^2-2ab+b^2)/a〔[(a^2-b^2)/a〕/[(a-(2ab-b^2)/a]=〔[(a^2-b^2)/a〕/{[(a^2-(2ab-b^
2a²+3ab+b²-a²-ab-2b²=2a²-a²-2b²+b²+3ab-ab=a²-b²+2a
-1/3(3a²-6ab)+[a²-1/2(2a+2ab)]=-a²+2ab+a²-a-ab=ab-a=-1/2a-a=-3/2a你哪里抄错了吧手机提问者在客户
(1/ab)(a+b-4/(a+b))ab=15a-b=2(a-b)^2=4(a+b)^2=(a-b)^2+4ab=64a+b=8(ab=15>0,a-b=2>0所以a+b>0)(1/ab)(a+b-
原式=[a-2a(a+2)-a-1(a+2)2]•a+2a-4=a2-4-a2+aa(a+2)2•a+2a-4=a-4a(a+2)2•a+2a-4=1a(a+2).当a=2-1时,原式=1(2-1)(
原式=4ab+3a²-ab+b²-3ab-2b²=(4ab-ab-3ab)+3a²+(b²-2b²)=3a²-b²当a=
(a²+ab-ac)/(a²-ab)·[(a-b)²-c²]/(a²+2ab+b²)÷[a²-(b-c)²]/(b&su
/>化简:原式=3ab-2(a²-ab)-(a²-ab)=3ab-2a²+2ab-a²+ab=-3a²+6ab求值:原式=-3a²+6ab=
原式=5ab-6ab+8ab2+12ab-5ab2=-12ab+3ab2,当a=12,b=-23时,原式=16+23=56.
原式=-(9a^4-18a^3+3b^2+4a^3b)=-(9a^4-14a^3b+3b^2)=-(9*1-14*(-1)^3*(-2)+3*(-2)^2)=-(9-28+12)=7
原式=2a^2b+2ab^2-2ab^2+1-a^2b-2=2a^2b-a^2b+2ab^2-2ab^2-1=a^2b-1
-a²b+(3ab²-a²b)-2(2ab²-a²b)=-a²b+3ab²-a²b-4ab²+2a²