已知a b=7,a-b=3
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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
解a²+ab=3①b²+ab=7②②×2得:2b²+2ab=14③①-③得:a²-ab-2b²=3-14=-11
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
a-3ab+b/2a+2b-7ab分子分母同除以ab=(a/ab-3ab/ab+b/ab)/(2a/ab+2b/ab-7ab/ab)=(1/b-3+1/a)+(2/b+2/a-7)=[(1/a+1/b
(a-b)²=37a²-ab+b²=40(a-b)²=a²-2ab+b²=a²+2ab+b²-4ab=(a+b)
a^2+ab=3,b^2+ab=7a^2-ab-2b^2=a^2+ab-2ab-2b^2=(a^2+ab)-2(ab+b^2)=3-2×7=-11
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
1/a+1/b=7(a+b)/ab=7a+b=7ab原式=[(a+b)-4ab]/[2(a+b)-3ab]=(7ab-4ab)/(2×7ab-3ab)=3ab/11ab=3/11
1/a+1/b=3通分可得(a+b)/(ab)=3a+b=3ab(2a-3ab+2b)/(9a+7ab+9b)=[2(a+b)-3ab]/[9(a+b)+7ab]=(2×3ab-3ab)/(9×3ab
a^2b+ab^2=ab(a+b)=21(a+b)^2=7^2a^2+b^2+2ab=49a^2+b^2=49-6=43
(5ab+4a+7b)+(6a-3ab)-(4ab-3b)=5ab+4a+7b+6a-3ab-4ab+3b=-2ab+10a+10b=-2ab+10(a+b)∵a+b=17,ab=10∴原式=-2×1
-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
2(a^2-b)-2(ab-b^2)-(a^2-3ab-7b)-2b^展开得:原式=a^2+ab+5b=a(a+b)+5b=5a+5b=5(a+b)=25
a²-ab-2b²=a²+ab-ab-ab-2b²=(a²+ab)-2(ab+b²)=3-2x7=-9
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.
a²+2ab+b²=(a+b)²=(-3)²=9
(a+b)²=49a²+2ab+b²=49把ab=12代入a²+24+b²=49得:a²+b²=25所以,a²-ab+b
(1)将其提取因式ab,原式=ab(a2+2-b2)=2(a2+2-b2),而将a+b平方再减去4ab,得(a-b)的平方=41,则a-b=根号41,再代入原式可得答案:4+14根号41(2)因为n(