Power delivered by battery in simple RL circuit

[Taulant Sholla]

Homework Statement

For a simple series LR circuit, find the energy delivered to the circuit by the battery.

Homework Equations

I = (V/R)*(1-e^-Rt/L)
P=IV
E=∫Pdt

The Attempt at a Solution

Isn't ∫ Pdt = ∫ IVdt = ∫ (V²/R)*(1-e^-Rt/L)dt = (V²/R)(t + (L/R)e^-Rt/L) ?

The book provides the answer, via a sample problem, of:

What am I missing?

 

[Taulant Sholla]

Oops - sorry - disregard the original post.