Illustrated · 1 min
The parabola with the equation is very similar to its parent function (the function without any modifications): .
First we have to understand what the coefficient does to the parent function:
Let us write down some values for the parabola and parent function.
$y=x^2: \ \dots;(-3,9);(-2,4);(-1,1);(0,0);(1,1);(2,4);(3,9);\dots \
y=ax^2: \ \dots;(-3,9a);(-2,4a);(-1,1a);(0,0);(1,1a);(2,4a);(3,9a);\dots$
As you can see, is simply has a value times more than . In a more graphical sense, the graph of the parabola is the parent function stretched.
The green plot is the parent function while the blue function is the parabola with . Note how the vertex is the same for both functions.