k^2-6*k+9=0 equation
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The solution
Detail solution
This equation is of the form
a*k^2 + b*k + c = 0
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$k_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$k_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 1$$
$$b = -6$$
$$c = 9$$
, then
D = b^2 - 4 * a * c =
(-6)^2 - 4 * (1) * (9) = 0
Because D = 0, then the equation has one root.
k = -b/2a = --6/2/(1)
$$k_{1} = 3$$
Vieta's Theorem
it is reduced quadratic equation
$$k^{2} + k p + q = 0$$
where
$$p = \frac{b}{a}$$
$$p = -6$$
$$q = \frac{c}{a}$$
$$q = 9$$
Vieta Formulas
$$k_{1} + k_{2} = - p$$
$$k_{1} k_{2} = q$$
$$k_{1} + k_{2} = 6$$
$$k_{1} k_{2} = 9$$
Sum and product of roots
[src]
$$3$$
$$3$$
$$3$$
$$3$$