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## Homework Statement

differential equation

(dr/dy)+r=8 ; r(1)=0.3

## The Attempt at a Solution

(dr/dy)=(8-r)

∫[dr/(8-r)]=∫dy

ln|8-r|+c1=y+c2 ; k=c2-c1

ln|8-r|=y+k ; r(1)=0.3

then take of e^ both sides which gives

8-r=e^(y+k)

8-e^(y+k)=r and we know r(1)=0.3 which means 0.3=8-e^(1+k); then solve for k

k=ln|7.7|-1 then when plug this into r(y)= 8-e^(y+k) for some reason webassign says

r(y)= 8-7.7*e^(1-y)

but i get r(y)=8-7.7*e^(y-1) are they equivalent

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