f(x)=ex+∫01(y+xex)f(y)dySplitting the integral:
f(x)=ex+∫01yf(y)dy+xex∫01f(y)dyLet
A=∫01yf(y)dy and
B=∫01f(y)dy⇒f(x)=(1+Bx)ex+AAt
x=0:
f(0)=1+ANow compute
B using the expression for
f(y):
B=∫01[(1+By)ey+A]dyB=∫01eydy+B∫01yeydy+∫01AdyEvaluating each integral:
∫01eydy=e−1∫01yeydy=[yey]01−∫01eydy=e−(e−1)=1∫01Ady=A⇒B=(e−1)+B(1)+A⇒0=e−1+A⇒A=1−ef(0)=1+A=1+(1−e)=2−ee+f(0)=e+(2−e)=2Answer:
2