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1.ab(c^2-d^2)-cd(a^2-b^2)2.x^4+x^3+6x^2+5x+53.x^2(y-z)+y^2(z-x)+z^2(x-y)4.a为正数a[a(a+b)+b]+b=1求a+b=5.x+1/x=t求x^3+1/x^3=6若a=(2+1)(2^4+1)(2^8+1)(2^16+1)(2^64+1)则a-2002=7.(c^2-b^2+d^2-a^2)-4(ab-cd)^28.不等实数mn满

题目详情
1.ab(c^2-d^2)-cd(a^2-b^2)
2.x^4+x^3+6x^2+5x+5
3.x^2(y-z)+y^2(z-x)+z^2(x-y)
4.a为正数a[a(a+b)+b]+b=1求a+b=
5.x+1/x=t 求x^3+1/x^3=
6若a=(2+1)(2^4+1)(2^8+1)(2^16+1)(2^64+1)则a-2002=
7.(c^2-b^2+d^2-a^2)-4(ab-cd)^2
8.不等实数mn满足m^2+2m=a n^2+2n=a m^2n^2=3求实数绝对值下a的值
补充:n^2=n的二次方,m^10=m的十次方依此类推 1、2、3、7为分解因式
▼优质解答
答案和解析
ab(c^2-d^2)-cd(a^2-b^2)
=abc^2-abd^2-a^2cd+b^2cd
=(abc^2-a^2cd)-abd^2+b^2cd
=ac(bc-ad)+bd(bc-ad)
=(bc-ad)(ac+bd)
x^4+x^3+6x^2+5x+5
=x^2(x^2+x+1)+5(x^2+x+1)
=(x^2+5)(x^2+x+1)
x^2(y-z)+y^2(z-x)+z^2(x-y)
=x^2(y-z)+(y^2z-yz^2)+(xz^2-xy^2)
=x^2(y-z)+yz(y-z)-x(y+z)(y-z)
=(y-z)(x^2+yz-xy-xz)
=(y-z)[(x^2-xy)+(yz-xz)]
=(y-z)[x(x-y)+z(y-x)]
=(y-z)(x-y)(x-z)
a[a(a+b)+b]+b=1
a[a(a^2+ab+b)+b]+b=1
a^4+a^3b+a^2b+ab+b-1=0
b(a^3+a^2+a+1)+a^4-1=0
b(a^2+1)(a+1)+(a^2+1)(a+1)(a-1)=0
(a^2+1)(a+1)(a+b-1)=0
a为正数,
(a^2+1)>0
(a+1)>0
那a+b=1
(X+1/X)=t
X^3+1/X^3=(X+1/X)[(X+1/X)^2-3]
=t(t^2-3)
=t^3-3t
a=(2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1)(2^32+1)(2^64+1)
=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1)(2^32+1)(2^64+1)
=(2^2-1)(2^2+1)(2^4+1)(2^8+1)(2^16+1)(2^32+1)(2^64+1)
=(2^4-1)(2^4+1)(2^8+1)(2^16+1)(2^32+1)(2^64+1)
=(2^8-1)(2^8+1)(2^16+1)(2^32+1)(2^64+1)
=(2^16-1)(2^16+1)(2^32+1)(2^64+1)
=(2^32-1)(2^32+1)(2^64+1)
=(2^64-1)(2^64+1)
=2^128-1
则a-2002=2^128-1-2002=2^128-2003
(c^2+d^2-b^2-a^2)^2-4(ab-cd)^2
=(c^2+d^2-b^2-a^2)^2-(2ab-2cd)^2
=(c^2+d^2-b^2-a^2-2ab+2cd)(c^2+d^2-b^2-a^2+2ab-2cd)
=[(c+d)^2-(a+b)^2][(c-d)^2-(a-b)^2]
=(c+d+a+b)(c+d-a-b)(c-d+a-b)(c-d-a+b)
=(a+b+c+d)(c+d-a-b)(a+c-b-d)(b+c-a-d)
由题意知:m、n是方程x^2+2x-a=0的两个不等实根
则由韦达定理知:m+n=-2,mn=-a
则(m+n)^2=m^2+n^2+2mn
即:4=3-2a
所以a=-1/2,a的绝对值为1/2