1. If the following equation has two unequal real roots, find the range of values of k.
x^2+3x-k-1=0
Please answer the above question and show the steps clearly, thank you!!!
If you are not sure how to do this question, please do not answer it, thank you!!!
Quadratic Equations (20marks) Urgent!!!!!!!!!!!!!
2007-09-15 8:24 pm
回答 (2)
2007-09-15 8:30 pm
✔ 最佳答案
x2 + 3x – k – 1 = 0 Since the equation has two unequal real root,
So, dicriminant > 0
i.e. (3)2 – 4(1)(-k - 1) > 0
9 + 4k + 4 > 0
4k > -13
k > -13/4
參考: Myself~~~
2007-09-15 9:58 pm
the equation has two unequal real roots
(i.e. discriminant > 0)
so
b^2-4ac >0
=> 3^2 - 4 (1)(-k-1) > 0
=> 9+4k+4>0
=> k >13/4
absolutely sure and these are the full steps!
2007-09-15 13:59:28 補充：
it's -13/4 i miss the negative sign above~
(i.e. discriminant > 0)
so
b^2-4ac >0
=> 3^2 - 4 (1)(-k-1) > 0
=> 9+4k+4>0
=> k >13/4
absolutely sure and these are the full steps!
2007-09-15 13:59:28 補充：
it's -13/4 i miss the negative sign above~
參考: my brain
收錄日期: 2021-04-20 20:03:21
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