请教几道数学题目~~谢谢
\u95ee\u51e0\u9053\u6570\u5b66\u98981.x+2.6=3.8
x=3.8-2.6
x=1.2
2.23.2-x=8
x=23.2-8
x=15.2
3.5x=1.25
x=1.25/5
x=0.25
4.3x+12=60
3x=60-12
3x=48
x=48/3
x=16
5.30+x=45.2
x=45.2-30
x=15.2
6.10-3\u5206\u4e4b1x=5\u5206\u4e4b1
3fenzhi1x=10-5\u5206\u4e4b\u4e00
\u4e09\u5206\u4e4b\u4e00x=9\u53c85\u5206\u4e4b\u4e00
x=5\u5206\u4e4b138
7.3x+x=3.6
4x=3.6
x=3.6/4
x=0.9
1\u3002\u4e00\u4e2a\u6570\u76845\u500d\u518d\u52a0\u4e0a5\u6b63\u597d\u662f100\u8fd9\u4e2a\u6570\u662f\u591a\u5c11\uff1f\uff08\u65b9\u7a0b\u89e3\uff09
\u89e3\uff1a\u8bbe\u8fd9\u4e2a\u6570\u662fx
5x+5=100
5x=100-5
x=95\u00f75
x=19
2\u3002\u4e00\u4e2a\u6570\u76848\u500d\u4e0e\u5b834\u5206\u4e4b1\u7684\u548c\u662f66\uff0c\u8fd9\u4e2a\u6570\u662f\u591a\u5c11\uff1f\uff08\u65b9\u7a0b\u89e3\uff09
\u89e3\uff1a\u8bbe\u8fd9\u4e2a\u6570\u662fx
8x+1/4x=66
x=66\u00f78.25
x=8
3\u3002\u7532\u4e59\u4e24\u4e2a\u5de5\u7a0b\u961f\u540c\u4fee\u4e00\u6761\u516c\u8def\uff0c\u5b83\u4eec\u4ece\u4e24\u7aef\u540c\u65f6\u65bd\u5de5\u3002
\uff081\uff09\u7532\u961f\u6bcf\u5929\u4feea\u7c73\uff0c\u4e59\u961f\u6bcf\u5929\u4feeb\u7c73\uff0c8\u5929\u4fee\u5b8c\u3002\u8fd9\u6761\u516c\u8def\u957f\u591a\u5c11\u7c73?(\u65b9\u7a0b\u89e3\uff09
\u89e3\uff1a\u8bbe\u8fd9\u6761\u516c\u8def\u957fx\u7c73
x\u00f78=a+b
\u5bf9\u4e0d\u8d77\uff0c\u6211\u89e3\u4e0d\u51fa\u6765\uff0c\u6ca1\u6570\u636e\uff01
\uff082\uff09\u5982\u679c\u8fd9\u6761\u516c\u8def\u957f3000\u7c73\uff0c\u7532\u961f\u6bcf\u5929\u4fee85\u7c73\uff0c\u4e59\u961f\u6bcf\u5929\u4fee65\u7c73\u3002\u4fee\u5b8c\u8fd9\u6761\u516c\u8def\u9700\u8981\u51e0\u5929\uff1f\uff08\u65b9\u7a0b\u89e3\uff09
\u89e3\uff1a\u8bbe\u4fee\u5b8c\u8fd9\u6761\u516c\u8def\u9700\u8981y\u5929
\uff0885+65\uff09y=3000
y=3000\u00f7150
y=20
\u7b54\uff1a\u4fee\u5b8c\u8fd9\u6761\u516c\u8def\u898120\u5929
\u95ee\u4e00\u4e0b\uff0c\u4f60\u51e0\u5e74\u7ea7\u4e86\uff1f
2.(n+2)^2=n^2+4(n+1)
3.(1+1/2)*(1+1/2^2(二的二次方分之一)*(1+1/2^4)*(1+1/2^8)*1/2^15
=(1-1/2)*(1+1/2)*(1+1/2^2(二的二次方分之一)*(1+1/2^4)*(1+1/2^8)*1/2^15*1/(1-1/2)
=(1-1/2^16)/[2^15*(1-1/2)]
=(1-1/2^16)/2^16
=1/2^16-1/2^32
100^2-99^2+98^2-97^2……+2^2-1
=(100+99)(100-99)+(98+97)(98-97)+...+(2+1)(2-1)
=199+195+191+...+3
=(3+199)*50/2
=5050
4.x^2-3x+1=0,X=0不是它的解，所以X不=0，
等式两边都除以X，得
x-3+1/x=0
x+1/x=3
2)x^2+1/x^2=(x+1/x)^2-2x*1/x
=(x+1/x)^2-2=9-2=7
1、计算100^2-99^2+98^2-97^2+96^2-95^2+……2^2-1^2=________
=(100+99)*(100-99)+(98+97)*(98-97)+(96+95)*(96-95)+...+(2+1)(2-1)
=199+195+191+...+3
=(199+3)*50/2
=5050
1.X^2-Y^2=(X+Y)(X-Y)=(X+Y)*5=55
so:X+Y=11
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