x^2 - 4x - 12 < 0 ?

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answers:
sepia say: x^2 - 4x - 12 < 0
Solution:
-2 < x < 6
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Krishnamurthy say: x^2 - 4x - 12 < 0
Solution:
-2 < x < 6
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Como say: ( x - 6 ) ( x + 2 ) < 0

___________________- 2____________6__________
x - 6_______-ve__________-ve______0____+ve__...
x + 2_______-ve_____0____+ve_____0____+ve___...
product_____+ve____0____-ve______0____+...

Solution set
{ x : - 2 < x < 6 }
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Jeff Aaron say: What about it?

If you want to solve for X:
X^2 < 4x + 12
-sqrt(4x + 12) < X < sqrt(4x + 12)

If you want to solve for x:
4x > X^2 - 12
x > 0.25X^2 - 3
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la console say: x² - 4x - 12 < 0

x² - (6x - 2x) - 12 < 0

x² - 6x + 2x - 12 < 0

(x² - 6x) + (2x - 12) < 0

x.(x - 6) + 2.(x - 6) < 0

(x + 2).(x - 6) < 0 → the roots are: - 2 ; 6 → then you make a table


x_____-∞_____-2_____6_____+∞
(x + 2)_____-__0___+_____+
(x - 6)_____-_______-__0__+
sign______+___0___-__0__+

…and you can see when the sign is < 0

x Є ] - 2 ; 6 [
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khalil say: x² - 4x - 12 = 0
x = 2 ± √2² + 12 / 1
x = 6 or -2
(x -6 ) ( x + 2 ) < 0
note .. the signs were changed

there are three parts
1) -∞ < x < -2
x - 6 < 0 and x + 2 < 0 .....result > 0

2) -2 < x < 6
x - 6 < 0 and x + 2 > 0 ......result < 0 ....◄◄◄ the answer

3) 6 < x < +∞
x -6 > 0 and x + 2 > 0 .....result > 0
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tbuil say: divignuj
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hatlb say: nzksihxk
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xiifw say: yydpxthw
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