y(x)=∫(0,x) y(t)dt+x+1,y(0)=1
两边求导得y'=y+1
即dy/dx=y+1
分离变量
dy/(y+1)=dx
两边积分
∫dy/(y+1)=∫dx
得ln(y+1)=x+C1
通解:y+1=Ce^x
初始条件y(0)=1,得C=2
所以y(x)=2e^x-1
∫(0->x)(x-t)y(t)dt=2x+ ∫(0->x) y(t)dt
x∫(0->x) y(t) dt -∫(0->x)ty(t)dt =2x+ ∫(0->x) y(t)dt
两边求导
∫(0->x) y(t) dt + xy(x) -xy(x) =2x+ y(x)
∫(0->x) y(t) dt =2x+ y(x)
x=0
y(0) = 0
两边求导
y(x) =2+ y'(x)
y'(x) - y = -2
yp = C
yp' =0
yp' - yp = -2
-C =-2
C=2
ie
y= Ae^x + 2
y(0) = A+2 =0
=> A=-2
y= -2e^x + 2