实数a满足a²-4a+2=-1/a²+4/a.1、试求a+1/a的值.2、试求a²/(2a²-4-4a²×a²) 2小问最后是4乘(a的四次方),
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![实数a满足a²-4a+2=-1/a²+4/a.1、试求a+1/a的值.2、试求a²/(2a²-4-4a²×a²) 2小问最后是4乘(a的四次方),](/uploads/image/z/10382879-47-9.jpg?t=%E5%AE%9E%E6%95%B0a%E6%BB%A1%E8%B6%B3a%26%23178%3B-4a%2B2%3D-1%2Fa%26%23178%3B%2B4%2Fa.1%E3%80%81%E8%AF%95%E6%B1%82a%2B1%2Fa%E7%9A%84%E5%80%BC.2%E3%80%81%E8%AF%95%E6%B1%82a%26%23178%3B%2F%282a%26%23178%3B-4-4a%26%23178%3B%C3%97a%26%23178%3B%EF%BC%89+2%E5%B0%8F%E9%97%AE%E6%9C%80%E5%90%8E%E6%98%AF4%E4%B9%98%EF%BC%88a%E7%9A%84%E5%9B%9B%E6%AC%A1%E6%96%B9%EF%BC%89%2C)
实数a满足a²-4a+2=-1/a²+4/a.1、试求a+1/a的值.2、试求a²/(2a²-4-4a²×a²) 2小问最后是4乘(a的四次方),
实数a满足a²-4a+2=-1/a²+4/a.1、试求a+1/a的值.2、试求a²/(2a²-4-4a²×a²)
2小问最后是4乘(a的四次方),
实数a满足a²-4a+2=-1/a²+4/a.1、试求a+1/a的值.2、试求a²/(2a²-4-4a²×a²) 2小问最后是4乘(a的四次方),
1、a²-4a+2=-1/a²+4/a
a²+2+1/a²=4a+4/a
(a+1/a)²=4(a+1/a)
a+1/a=4
a²+1/a²=16-2=14
2、a²/(2a²-4-4a²×a²)
=1/(2-4a²-4/a²)
=1/[2-4(a²+1/a²)]
=1/(-54)
=-1/54
最先回答,
a+1/a=4 第二题-1/54
1
两边同除以a²,整理后1/a4-4/a3+2/a²-4/a+1=0
(1/a²+1)(1/a²-4/a+1)=0
1/a²-4/a+1=0
(1/a-2)^2=1/a²-4/a+4=3
a+1/a=4
2
a²/(2a²-4-4a²×a²)...
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1
两边同除以a²,整理后1/a4-4/a3+2/a²-4/a+1=0
(1/a²+1)(1/a²-4/a+1)=0
1/a²-4/a+1=0
(1/a-2)^2=1/a²-4/a+4=3
a+1/a=4
2
a²/(2a²-4-4a²×a²)=1/(2-4/a²-4a²)=1/(2-4*14)=-1/54
(a+1/a)^2=16=a²+1/a²+2
a²+1/a²=14
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