已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2单调性已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2)讨论f(x)的单调性

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已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x(m属于[0,0.5])(1)求an(2单调性已知数列{an}满足a1=t>1,a(n+1

已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2单调性已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2)讨论f(x)的单调性
已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2单调性
已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2)讨论f(x)的单调性

已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2单调性已知数列{an}满足a1=t>1,a(n+1)=(n+1)an/n,函数f(x)=ln(1+x)+mx^2-x (m属于[0,0.5]) (1)求an (2)讨论f(x)的单调性
(1)a(n+1)/an=1+1/n,代入a1=t
则a2=2t a3=3t a4=4t
则{an}是一个以t为首项 公差为t的等差数列
an=nt(n+1)/2
(2)f'(x)=1/x+1+2mx-1
当f’(x)>0时为单调递增 所以f‘(x)=2mx2+2mx+1/x+1
解得:f(x)单增区间为[-1,+∞)