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# Math watch

1. Find the range of values of k for which x^2 +k(x+2) +3(x+1) >0 for all real values of x.
2. try to solve as you usually do with double brackets!
>0 take as = 0 but do write >0 when solving
3. try to get it in the form ax^2+bx+c>0 (quadratic equation), determine its discriminant Δ which is a function of k. Then solve Δ<0
Furthermore, working with double brackets keep in mind that not only the product of two positive numbers is greater than zero, but also the product of two negative ones.
4. (Original post by fatima1998)
try to solve as you usually do with double brackets!
>0 take as = 0 but do write >0 when solving
5. (Original post by B_9710)
but isn't this just a simple algebra but they put that sign to make it complicated!
6. (Original post by fatima1998)
but isn't this just a simple algebra but they put that sign to make it complicated!
Not at all!
7. (Original post by Zacken)
Not at all!
oops!! i misunderstood the question
i thought the question is to find the value of x but it's values of the k

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Updated: March 5, 2016
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