Existence, Uniqueness & Bifurcations · Easy problem

Apply one step of Picard iteration to $y' = 2t - y$, $y(0) = 1$, starting from $\varphi_0(t) = 1$ and using $\varphi_1(t) = 1 + \displaystyle\int_0^t \big(2s - \varphi_0(s)\big)\,ds$. Evaluate $\varphi_1(3)$.