To plot the parabola defined by the equation y = x^2 + 2x + 3 for the range -20 < x < 20 in Matlab, the following code can be used: x = -20:0.01:20; y = x.^2 + 2*x + 3; plot(x,y); This code can be directly copied into the Matlab Command Prompt. For further learning, users are encouraged to explore Matlab Help and the MathWorks website for additional resources. The discussion also notes that while simple questions can be addressed directly, it's important to engage with the community for deeper understanding, especially in homework contexts.