Let \(f(t,x):\mathbb {R}\times \mathbb {R}^n\to \mathbb {R}^n\) be a continuously differentiable function. Show that there is an \(\epsilon >0\) and
a unique continuously differentiable function \(y(t)\in \mathbb {R}^n\) for \(t\in [0,\epsilon ]\) that satisfies the initial
value problem \[ \frac {dx}{dt}=f(t,x),\qquad x(0)=x_0. \]
Construct the first few Picard iterates for the differential equation \[ \dot {x}=2t-\sqrt {\max (0,x)},\qquad x(0)=0. \tag {1} \] Show
that the Picard iterates do not converge. Why do they not converge?