An extraordinarily quick way to sketch quadratics
Students in an algebra class spend many a week learning to sketch graphs of
quadratic functions:
y = ax2 + bx + c
And students are usually taught to memorise the following:
The graph is an upward or downward U-shaped graph (called a parabola)
depending on whether the leading coefficient a is positive or negative.
And the vertex of the parabola occurs at: x = – (b/2a)
Plugging in this value of x into gives the y-coordinate of the vertex and plugging in other values of x will help ascertain the correct “steepness” of the U-shape.
My first piece of advice: FORGET THE FORMULA FOR THE VERTEX!
Memorising is joyless!
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An extraordinarily quick way to sketch quadratics