因为f(x+y)=f(x)f(y),f(a(n+1))=f(an)f(2),所以a(n+1)=an+2
T2n=(a2-a1)(a2+a1)+(a4-a3)(a4+a3)+....+(a2n-a(2n-1))(a2n+a(2n-1))
=2(a1+a2+a3+.....a2n)=2n(a1+a2n)=2n(2a1+2(2n-1))=8n²
所以(T2n...
因为f(x+y)=f(x)f(y),f(a(n+1))=f(an)f(2),所以a(n+1)=an+2
T2n=(a2-a1)(a2+a1)+(a4-a3)(a4+a3)+....+(a2n-a(2n-1))(a2n+a(2n-1))
=2(a1+a2+a3+.....a2n)=2n(a1+a2n)=2n(2a1+2(2n-1))=8n²
所以(T2n...