若a+1/a=2,则a2+1/a2的值是,a4+1\a4的值是.a4-1/a4的值是

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若a+1/a=2,则a2+1/a2的值是,a4+1\a4的值是.a4-1/a4的值是
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若a+1/a=2,则a2+1/a2的值是,a4+1\a4的值是.a4-1/a4的值是
若a+1/a=2,则a2+1/a2的值是,a4+1\a4的值是.a4-1/a4的值是

若a+1/a=2,则a2+1/a2的值是,a4+1\a4的值是.a4-1/a4的值是
a^2+1/a^2=(a+1/a)^2-2=2
a^4+1/a^4=(a^2+1/a^2)^2-2=2

a2+1/a2
=(a+1/a)^2-2
=4-2
=2
a4+1\a4
=(a2+1/a2)^2-2
=4-2
=2
a^4-2+1/a^4
=(a^2-1/a^2)^2
=2-2
=0
a^4-1/a^4
=(a^2+1/a^2)(a^2-1/a^2)
=2*0
=0

a+1/a=2, 平方
a^2+2+1/a^2=4
a2+1/a2=2 平方
a^4+2+1/a^4=4
a4+1\a4=2
因为
a+1/a>=2 所以a=1
a4-1/a4=0

∵a+1/a=2,
∴a^2-2a+1=0
∴(a-1)^2=0
∴a=1
∴a^2+1/a^2=2
a^4+1/a^4=2
a^4-1/a^4=0