$L(\lambda) = \lambda^{150}e^{-3\lambda}$
$L’(\lambda) = 150 \lambda^{149} e^{-3\lambda} - 3\lambda^{150} e^{-3\lambda}$
$L’(\lambda) = 3\lambda^{149}e^{-3\lambda} (50-\lambda)$
note ...
if $L’ = uvw$, where $u,v, \text{ and } w$ are all functions of $\lambda$, then ...
$L’’ = u’vw + uv’w + uvw’$
give it a go ...