2.How to form a quadratic equation???

If the roots of the equation are 1 and 2? Well, we can do the work out like this using the reverse method:

We can assume:

x = 1 or x = 2

(x –1) = 0 or (x –2) = 0

(x -1)(x -2)=0

x² -2x-x +2=0

x² -3x +2=0

So the quadratic equation is x2 – 3x + 2=0. This is the most basic technique to form up a quadratic equation!!

Let’s doing the same ways, assume we have the roots of α,alpha and β,beta:

In other words, we can form up the equation using the sum of roots (SOR) and product of roots (POR). If the roots are 1 and 2,

SOR = 1+2

= 3

POR = 1 x 2

=2

Exercise: (teks)

3.Determine the conditions for the type of roots

Example: A quadratic equation x2+2hx+a=xhas two equal roots. Find the possible values of h.