Past exam of the MPhil in nuclear energy course of the University of Cambridge / 2021 / Module NE1 / 2 / f / ii / Solution

The precursor exponential from part (e) has inverse period $\rho \lambda /(\beta -\rho )$. HenceThis is approximately $0.96\%$ shorter than the exact dominant period, so it slightly overestimates growth for these stipulated constants. Neglecting the small $\Lambda$ contribution is more accurate here than replacing the complete frequency dependence by its tangent at the origin.