|x-1+|x-2|+|x+3|+|x+4|+...+|x-99|的最小值是多少_作业帮
|x-1+|x-2|+|x+3|+|x+4|+...+|x-99|的最小值是多少
用数轴做两点之间的距离算出来3872
得用绝对值的几何意义可得出，x=50时就是最小的值，2450.如果你是高中的学生还可以用绝对值不等式做。计算(x+4)/(x+1)+(x-2)/(x-3)-(x-4)/(x-1)-(x+2)/(x+3)_作业帮
计算(x+4)/(x+1)+(x-2)/(x-3)-(x-4)/(x-1)-(x+2)/(x+3)
(x+4)/(x+1)+(x-2)/(x-3)-(x-4)/(x-1)-(x+2)/(x+3)=【(x+4)/(x+1)-(x-4)/(x-1)】+【(x-2)/(x-3)-(x+2)/(x+3】=6x/(x²-1)
2x/(x²-9)=8x(x²-7) / [(x²-1)(x²-9)]
(x+4)/(x+1)+(x-2)/(x-3)-(x-4)/(x-1)-(x+2)/(x+3)=1+3/(x+1)+1+1/(x-3)-1+3/(x-1)-1+1/(x+3)=3/(x+1)+3/(x-1)+1/(x-3)+1/(x+3)=(3x-3+3x+3)/(x²-1)+(x+3+x-3)/(x²-9)=6x/(x²-1)...
(x+4)/(x+1)+(x-2)/(x-3)-(x-4)/(x-1)-(x+2)/(x+3)=1+1-1-1+3/(x+1)+1/(x-3)+3/(x-1)+1/(x+3)=3/(x+1)+3/(x-1)+1/(x+3)+1/(x-3)=6x/(x²-1)+6x/3(x²-9)=6x(1/(x²-1)+1/3(x²-9))=8x(x²-7)/[(x²-1)(x²-9)]y=(x-1)(x-2)(x+3)(x+4)+6 求值域_作业帮
y=(x-1)(x-2)(x+3)(x+4)+6 求值域
y=【(x-1)(x+3)】【(x-2)(x+4)】+6 =(x^2+2x-3)(x^2+2x-8)+6令x^2+2x-3=t t=(x+1)^2-4>=-4y=(t)(t-5)+6=t^2-5t+6=(t-5/2)^2-1/4t=(x+1)^2-4>=-4时 y>=-1/4即值域为【-1/4,+∞)
y=(x^2+2x-3)(x^2+2x-8)+6令x^2+2x=t
t=(x+1)^2-1>=-1y=(t-3)(t-8)+6=t^2-11t+30=(t-11/2)^2-1/4>=-1/4
y=【(x-1)(x+3)】【(x-2)(x+4)】+6 =(x^2+2x-3)(x^2+2x-8)+6令x^2+2x-3=t t=(x+1)^2-4>=-4y=(t)(t-5)+6=t^2-5t+6=(t-5/2)^2-1/4t=(x+1)^2-4>=-4时 y>=-1/4y=【(x-1)(x+3...
t=(x+1)^2-1>=-1
这个怎么得出来的？
=x^2+2x+1-1
=(x+1)^2-1
因为(x+1)^2>=0& 2013 - 2014 作业宝. All Rights Reserved. 沪ICP备号-9}