一元一次方程!急啊!会多给分的!拜托了!55555
1个回答

1/9{1/7[1/5((x+2)/3 +4)+6]+8}=1

1/7[1/5((x+2)/3 +4)+6]+8=9

1/7[1/5((x+2)/3 +4)+6]=1

1/5((x+2)/3 +4)+6=7

1/5((x+2)/3 +4)=1

(x+2)/3 +4=5

(x+2)/3 =1

x+2=3

x=1

(x-1.3)/2 -(8x-1.8)/1.2=(5x-0.4)/0.3 -x

1.2(x-1.3)-2(8x-1.8)=8(5x-0.4)-2.4x

1.2x-1.56-16x+3.6=40x-3.2-2.4x

52.4x=5.24

x=0.1

1-[ 1+1/2(1-x)]/3=4

[1+1/2(1-x)]/3=-3

1+1/2(1-x)=9

1/2(1-x)=8

1-x=16

x=-15

(0.4x+0.9)/0.5 -(0.03x+0.02)/0.03=(x-5)/2

6(0.4x+0.9)-100(0.03x+0.02)=1.5(x-5)

2.4x+5.4-3x-2=1.5x-7.5

2.1x=10.9

x=109/21=5又4/21

(0.1x-0.2)/0.02+(x+1)/5=-1

50(0.1x-0.2)+0.2(x+1)=-1

5x-10+0.2x+0.2=-1

5.2x=8.8

x=88/52=22/13=1又9/13

1/(1×2)+1/(2×3)+···+1/(2002×2003)+1/(2003×2004)+1/(2004×2005)

=1-1/2+1/2-1/3+...+1/2002-1/2003+1/2003-1/2004+1/2004-1/2005

=1-1/2005

=2004/2005