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the top of a parabola

Introduction

Empty Input Boxes can be used to insert the coordinates of a point in the same way as to type the result of a calculation. You only have to respect the appropriate syntaxes for points. In this worksheet we show the difference. Additionally we'll show some aternative ways to deal with randon numbers.

How to do this

  • parameters of parabola y = a (x - p)² + q: - factor a: Define the number a as a random number between -2 and 2 except 0 with the commands: lista = Shuffle({-2, -1, 1, 2}) and a = lista(1) - p and q: Define p = RandomBetween(-4, 4) and q = RandomBetween(-4, 4).
  • Solution: define a point Sol by using a capital to make sure it is a point and not a vector! Sol = (p, q)
  • The equation: We'll show the equation of the parabola in the form ax² + bx + c. Define f(x) = Polynomial(a (x - p)² + q) and use f in a dynamic text to show the equation of the parabola in the form ax² + bx + c.
  • Answer: define a number Ans to use as anwer and give it a value, that's certainly not the solution. Ans = (pi, pi). Again use a capital!
  • The rest goes exactly the same as when working with numbers instead of points.