Maths help Watch

wednesday_adams
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#1
Report Thread starter 4 years ago
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Can someone please tell me where I have gone wrong with this maths problem on discriminant and quadratic inequalities? It says

Find the range of values k for kx^2 -2xk-3k-12=0 to have real roots
so i did:
a=k
b-2k
c=-3k-12

(-2k)^2-4(k)(-3k-12)

4k^2+12K^2+48k

K^2+3k^2+12k
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Hasufel
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the 2nd bottom line, you`ve actually got 16k^{2}+48k

factor, and:

set >=0 and solve the inequality

(a graph helps, as you can SEE where the k function is below and above the x-axis)
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