To find the solutions for the equation x^2-4x+12 >
0.
We first factorise the left side expression
x^2-4x-12.
x^2-4x+12 =
x^2-6x+2x-12
x^2-4x+12 = x(x-6)
+2(x-6)
x^2-4x+12 = (x-6)
(x+2).
Therefore x^2-4x-12> 0 implies (x+2)(x-6) >
0.
Therefore both factors should be of the same
sign.
Therefore x+2 < 0 and x-6 < 0
,
Or (x+2)> 0 and (x-6) >
0.
This is possinble only when x < -2 Or x
> 6 , the x^2-4x-12 > 0.
Or x must be
in the interval (-infinity -2) Or in the interval (6 infinity).
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