已知a b=3c 1 2a-3b=-8c
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ab(a^2b^5-ab^3-b)=a^3b^6-a^2b^4-ab^2=(ab^2)^3-(ab^2)^2-ab^2=6³-6²-6=216-36-6=174
(3a-4b-ab)-(a-2b+3ab)=3a-4b-ab-a+2b-3ab=2a-2b-4ab=2(a-b)-4ab=2×(-1)-4×(-2)(将a-b=-1,ab=-2代入)=-2+8=6
则2a+2b+ab=2(a+b)+ab=2×3+6=6+6=12
ab^2=-2-ab(a^2b^5-ab^3-b)=-a^3b^6+a^2b^4+ab^2=-(ab^2)^3+(ab^2)^2+ab^2=-(-2)^3+(-2)^2+(-2)=8+4-2=10
ab^2=-6所以-ab(a^2*b^5-ab^3-b)=-a^3b^6+a^2b^4+ab^2=-(ab^2)^3+(ab^2)^2+(ab^2)=-(-6)^3+(-6)^2+(-6)=216+3
ab(36b-6b-b)=29ab^2=(30-1)*6=174
ab(ab^3+a^2b^5-b)=ab²(ab²+a²b^4-1)=6*(6+6²-1)=6*41=246
3a²b+3ab²=3ab(a+b)=3×3×4=36
(a+b)^2-5ab=9-10=-1
a-b=3ab2a-2b-ab/a-b+2ab=6ab-ab/3ab+2ab=5ab/5ab=1
-ab(a^2b^5-ab^3-b)=-a^3b^6+a^2b^4+ab^2=-(ab^2)^3+(ab^2)^2+ab^2=-(-3)^3+(-3)^2+(-3)=27+9-3=33
2a+2b-ab分之a+b+2ab=2(a+b)-ab分之a+b+2ab=6ab-ab分之3ab+2ab=5ab分之5ab=1
2a^2b+ab^2-3a^b+5ab-2ab^2-3ab=-a^2b-ab^2+2ab=-ab(a+b)+2ab=-10×1+2×10=10
ab+ba=a2+b2ab=(a+b)2−2abab,∵a+b=3,ab=1,∴(a+b)2−2abab=9-2=7,故答案为7.
a-b-3ab=0a-b=3ab(2a+3ab-2b)/(a-ab-b)=[2(a-b)+3ab]/(a-b-ab)=9ab/2ab=9/2
可以这么算a-b=1ab=23a+ab-3b=3(a-b)+2=3×1+2=5
ab/a+b=3ab=3(a+b)2ab/a+b-5(a+b)/ab=6(a+b)/(a+b)-5(a+b)/3(a+b)=6-5/3=13/3
ab/(a+b)=3,a+b=ab/3原式=[3(a+b)+ab]/[2(a+b)-ab]=[3(ab/3)+ab]/[2(ab/3)-ab]=2ab/(-ab/3)=-6