Chapter 8.3, Problem 3QCE

When using Euler's Method on the initial-value problem $y^{\prime }=f\left(x,y\right),y\left(x_0\right)=y_0,$ we obtain $y_n{}_{+1}$ from $y_n,x_n,$ and $\Delta x$ by means of the formula $y_n{}_{+1}=\text{\_\_\_\_\_}\text{.}$