数学题(先约分,再求值)1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]其中A^2+2A-1=0(3P^2-PQ)/(QP^2-6PQ+Q^2)其中P=1,Q= -2(^2代表平方)写清楚约分过程~~谢谢第2题原题就是这样的,我也觉得有问题
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![数学题(先约分,再求值)1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]其中A^2+2A-1=0(3P^2-PQ)/(QP^2-6PQ+Q^2)其中P=1,Q= -2(^2代表平方)写清楚约分过程~~谢谢第2题原题就是这样的,我也觉得有问题](/uploads/image/z/9326281-49-1.jpg?t=%E6%95%B0%E5%AD%A6%E9%A2%98%28%E5%85%88%E7%BA%A6%E5%88%86%2C%E5%86%8D%E6%B1%82%E5%80%BC%291%2F%28A%2B1%29-%5B%28A%2B3%29%2F%28A%5E2-1%29%5D%2A%5B%28A%5E2-2A%2B1%29%2F%28A%2B1%29%28A%2B3%29%5D%E5%85%B6%E4%B8%ADA%5E2%2B2A-1%3D0%283P%5E2-PQ%29%2F%28QP%5E2-6PQ%2BQ%5E2%29%E5%85%B6%E4%B8%ADP%3D1%2CQ%3D+-2%28%5E2%E4%BB%A3%E8%A1%A8%E5%B9%B3%E6%96%B9%29%E5%86%99%E6%B8%85%E6%A5%9A%E7%BA%A6%E5%88%86%E8%BF%87%E7%A8%8B%7E%7E%E8%B0%A2%E8%B0%A2%E7%AC%AC2%E9%A2%98%E5%8E%9F%E9%A2%98%E5%B0%B1%E6%98%AF%E8%BF%99%E6%A0%B7%E7%9A%84%2C%E6%88%91%E4%B9%9F%E8%A7%89%E5%BE%97%E6%9C%89%E9%97%AE%E9%A2%98)
数学题(先约分,再求值)1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]其中A^2+2A-1=0(3P^2-PQ)/(QP^2-6PQ+Q^2)其中P=1,Q= -2(^2代表平方)写清楚约分过程~~谢谢第2题原题就是这样的,我也觉得有问题
数学题(先约分,再求值)
1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]
其中A^2+2A-1=0
(3P^2-PQ)/(QP^2-6PQ+Q^2)
其中P=1,Q= -2
(^2代表平方)
写清楚约分过程~~谢谢
第2题原题就是这样的,我也觉得有问题
数学题(先约分,再求值)1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]其中A^2+2A-1=0(3P^2-PQ)/(QP^2-6PQ+Q^2)其中P=1,Q= -2(^2代表平方)写清楚约分过程~~谢谢第2题原题就是这样的,我也觉得有问题
1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]
=1/(A+1)-[(A+3)/(A+1)(A-1)]*[(A-1)^2/(A+1)(A+3)] (约分)
=1/(A+1)-(A-1)/(A+1)^2(通分)
=2/(A+1)^2
A^2+2A-1=0 得出 (A+1)^2=2
所以 2/(A+1)^2=2/2=1
1.解:约分
1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]
=1/(A+1)-[(A+3)/(A+1)(A-1)]*[(A-1)^2/(A+1)(A+3)]
=1/(A+1)-(A-1)/(A+1)^2
=2/(A+1)^2
因为A^2+2A-1=0 ,所以A=1
带入得:1/(A+1)-[(A+3)...
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1.解:约分
1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]
=1/(A+1)-[(A+3)/(A+1)(A-1)]*[(A-1)^2/(A+1)(A+3)]
=1/(A+1)-(A-1)/(A+1)^2
=2/(A+1)^2
因为A^2+2A-1=0 ,所以A=1
带入得:1/(A+1)-[(A+3)/(A^2-1)]*[(A^2-2A+1)/(A+1)(A+3)]
=2/(A+1)^2=1/2
2.
貌似不好约分
直接带(3P^2-PQ)/(QP^2-6PQ+Q^2) =5/14
是不是这样啊??
因为P=1,Q= -2
所以Q=-2P
再带入:
(3P^2-PQ)/(QP^2-6PQ+Q^2)
=5P^2/(16P^2-2P^3)
=5/(16-2P)
=5/(16-2)
=5/14
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先说第一题减号后面:
=(a+3)/(a+1)(a-1)*(a-1)^2/[(a+1)(a+3]
晕~你把它写道纸上,上下约分一下会得到:
=(a-1)/(a+1)^2
然后把1/(a+1)上下都乘以(a+1)就变成了:(a+1)/(a+1)^2
两个想减就是:(a+1)/(a+1)^2-(a-1)/(a+1)^2=2/(a+1)^2
解A^2+2A...
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先说第一题减号后面:
=(a+3)/(a+1)(a-1)*(a-1)^2/[(a+1)(a+3]
晕~你把它写道纸上,上下约分一下会得到:
=(a-1)/(a+1)^2
然后把1/(a+1)上下都乘以(a+1)就变成了:(a+1)/(a+1)^2
两个想减就是:(a+1)/(a+1)^2-(a-1)/(a+1)^2=2/(a+1)^2
解A^2+2A-1=0 得到a=1 带入2/(a+1)^2得到解为1/2
你再看看你写的第二道题写对没有?确定对了我再做我觉得有点儿问题
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