f(x) =1 + ∫[0,x] (x-t)f(t) dt

0)f(x) =1 + ∫[0,x] (x-t)f(t) dt
http://note.com/2036820/n/n96a4308873eb
0.1)f(0) =1

1)f(x) =1 +x ∫[0,x] f(t) dt - ∫[0,x] tf(t) dt
2)df/dx = ∫[0,x] f(t) dt +xf(x) -xf(x)
2.1)df/dx |(x=0) =0
3)d^2f/dx^2 =f(x)

4)f =c1 coshx +c2 sinhx
4.1) (0.1)c1 =1
4.2) (2.1)c2 =0
5)f(x) =coshx

10)微分方程式解法集3
http://plaza.rakuten.co.jp/kiyos06/diary/201706030000/