已知数列an满足an+1/an=n+2/n且a1=1,则an=

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已知数列an满足an+1/an=n+2/n且a1=1,则an=已知数列an满足an+1/an=n+2/n且a1=1,则an=已知数列an满足an+1/an=n+2/n且a1=1,则an=∵a(n+1)

已知数列an满足an+1/an=n+2/n且a1=1,则an=
已知数列an满足an+1/an=n+2/n且a1=1,则an=

已知数列an满足an+1/an=n+2/n且a1=1,则an=
∵a(n+1)/an=(n+2)/n,a1=1,
∴an=(n+1)/(n-1)*a(n-1)
=(n+1)n/[(n-1)(n-2)]*a(n-2)
.
=(n+1)n(n-1).4*3/[(n-1)(n-2).2*1]*a1
=n(n+1)/2

an=n/2,当n大于等于2时
an=1,当n=1

an=n(n+1)/2