已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________?

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已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________?

已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________?
已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________?

已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________?
∵ ax2=x(7-by),by2=y(7-ax) 相加:49=ax2+by2= 7x-bxy+7y-axy=7(x+y)-xy(a+b) ① 又:ax3=49x-bxy2,by3=49y-ax2y 相加得 133=ax3+by3=49(x+y)-xy(ax+by) 即49(x+y)-7xy=133 ,7(x+y)-xy=19 ② 同理ax4=133x-bxy3,by4=133y-ax3y 406=ax4+by4=133(x+y)-xy(ax2+by2) 即133(x+y)-49xy=406 ③ 由①、②、③联立,设x+y=u,xy=v 可得:x+y=2.5,xy=-1.5 ,a+b=21 带入得4996,是约等的

已知ax+by=7 ax²+by²=49 ax³+by³=133 ax^4+by^4=406已知ax+by=7 ax²+by²=49 ax³+by³=133 ax^4+by^4=406(1)求a+b ,x+y,xy的值(2)请问ax^5+by^5的值是有理数吗?(2)请问ax^5+by^5的值是有理数吗? 2(ax+by-ax)-(ax+by)^2-(by-ax)^2 其中a=-3 b=0.52(ax+by)(by-ax)-(ax+by)^2-(by-ax)^2 已知ax+by=7,ax+by=49,ax+by=133,ax四次方+by四次方=406.则2003(x+y)+6xy-2/17(a+b)的值为________? 已知ax+by=7,ax^2+by^2=49,ax^3+by^3=133,ax^4+by^4=406.求:2001(x+y)+6xy-17/2(a+b)的值 已知ax+by=7,ax^2+by^2=49,ax^3+by^3=133,ax^4+by^4=406,求2008(x+y)+2008xy+(a+b)/21的值 已知ax+by=7,ax^2+by^2=49,ax^3+by^3=133,ax^4+by^4=406.求:2008(x+y)+2008xy+(a+b)/21 已知ax+by=7ax^2+by^2=49ax^3+by^3=133ax^4+by^4=406试求1995(x+y)+6xy-17/2(a+b)的值过程要详细已知ax+by=7,ax^2+by^2=49,ax^3+by^3=133,ax^4+by^4=406 试求1995(x+y)+6xy-17/2(a+b)的值 2(ax+by)*(by-ax)-(ax+by)²-(by-ax)²,其中a=-3,x=2分之1 xoy平面上,ax+by=c,ax+by>c,ax+by》c,ax+by 已知ax-by-c=0的图像,且a 已知f(a,b)=ax+by,如果1 已知f(a.b)=ax+by,如果1 已知ax+by=3,ax²+by²=7,ax²+by³=16,ax^4+by^4=42,求ax^5+by^5的值 :设ax+by=7,ax^2+by^2=49,ax^3+by^3=133,ax^4+by^4=406试求:1995(x+y)+6xy-(17/2)(a+b)的值 实数a,b,x,满足ax+by=3,ax^2+by^2=7,ax^3+by^3=16,ax^4+by^4=42,ax^5+by^5=? 若a,b,x,y满足ax+by=3,ax^2+by^2=7,ax^3+by^3=16,ax^4+by^4=42,求ax^5+by^5的值 若a,b,x,y满足ax+by=3,ax+by=7,ax+by=16,ax的四次方+by的四次方=42,求ax的五次方+by的五次方的值 若a,b,x,y满足ax+by=3,ax^2+by^2=7,ax^3+by^3=16,ax^4+by^4=42,求ax^5+by^5的值