找规律题 若1/1X3+1/3X5+1/5X7+…+1/(2n-1)(2n+1)的值为17/35,求n的值.
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/06 19:28:38
找规律题 若1/1X3+1/3X5+1/5X7+…+1/(2n-1)(2n+1)的值为17/35,求n的值.
找规律题 若1/1X3+1/3X5+1/5X7+…+1/(2n-1)(2n+1)的值为17/35,求n的值.
找规律题 若1/1X3+1/3X5+1/5X7+…+1/(2n-1)(2n+1)的值为17/35,求n的值.
1/(2n-1)(2n+1)=1/2×(1/2n-1 +1/2n+1)
原式=1/2×(1-1/3+1/3-1/5+……+1/2n-1 -1/2n+1)
=n/2n+1=17/35
所以n=17
左边=1/2(1-1/3+1/3-1/5+1/5-1/7+....+1/(2n-1)-1/(2n-1)+1/(2n+1
右边=17/35
即 n/(2n+1)=17/35
n=17
1/1x3 + 1/3x5 +....+1/(2n-1)(2n+1) = (1/1 - 1/3 +1/3 -1/5 +......+1/(2n-1) - 1/(2n+1)) /2= (1 - 1/(2n+1)) / 2= 17/35 ---> n = 17.
因式分解:x5+x3+1
找规律:1乘1,1乘2,2乘3,3乘5,接下去1x1 ,1x2 ,2x3 ,3x5 ,( ),( ).找规律
找规律题 若1/1X3+1/3X5+1/5X7+…+1/(2n-1)(2n+1)的值为17/35,求n的值.
1x1 2x2 3x3 4x4 5x5```````nxn有什么规律
解一道方程组x1+x2+x3=5,x2+x3+x4=1,x3+x4+x5=-5,x4+x5+x1=-3,x5+x1+x2=2
x5-x4+x3-x2+x-1因式分解
X5-X4+X3+X2+X+1因式分解
1/1x3+1/2x4+1/3x5+
1/1x3+1/3x5+.+1/2005x2008
x1-x2+x3=1x2-x3+x4=21若x1,x2,x3,x4,x5满足方程组 x3-x4+x5=3x4-x5+x1=4x5-x1+x2=5求x2 x3 x4的值2已知 x1+x4+x6+x7=39 x2+x4+x5+x7=49 x3+x5+x6+x7=41 x4+x7=13 x5+x7=14 x6+x7=9 x1+x2+x3+x4+x5+x6+x7=9求x7的值若x1,x2,x3,x4,x5满足方程组 x1-x
3x5/3-5/3x3/1 怎么简算
若x1,x2,x3,x4,x5满足方程组:x1-x2+x3=1 x2-x3+x4=2 x3-x4+x5=3 x4-x5+x1=4 x5-x1+x2=5 求x2,x3,x4的少打了个字,是求x2,x3,x4的值
1x2+2x3+3x4+4x5+.+15x16
计算1x3+3x5+5x7+…+97x99
x1-x2+x3=1 x2-x3+x4=2 x3-x4+x5=3 x4-x5+x1=4 x5-x1+x2=5 求x1,x2,x3,x4,x5
数学智力乐园规律 1/1x2+1/2x3= 1/1x2+1/2x3+1/3x4= 1/1x2+1/2x3+1/3x4+1/4x5= 要规律
求解线性方程组 x1-2x2+3x3-x4-x5=2 x1+x2-x3+x4-2x5=1 2x1-求解线性方程组x1-2x2+3x3-x4-x5=2x1+x2-x3+x4-2x5=12x1-x2+x3-2x5=22x1+2x2-5x3+2x4-x5=5
一道简便计算数学题1X2+2X3+3X4+4X5...+n(n+1)一1X2+2X3+3X4+4X5...+2013X2014二写出规律三当n=4026为多少