 Two measurable cardinals under an ultrapower embedding

Let ${\kappa }_0<{\kappa }_1<\lambda$, where both ${\kappa }_i$ are measurable and $\lambda$ is inaccessible, and let $j_i:V_{\lambda }\to M_i$ be ultrapower embeddings by measures on ${\kappa }_i$. ThenThe second equality follows from the critical point. For the first, regularity gives continuity of $j_0$ at ${\kappa }_1$, while strong-limitness bounds $j_0(\beta )<{\kappa }_1$ for every $\beta <{\kappa }_1$.