If the roots of the equation 12x^2 + mx + 5 = 0 are real and equal then m is equal to
If the roots of the equation 12x2 + mx + 5 = 0 are real and equal then m is equal to
A) 4 \(\sqrt{15}\)
B) 2 \(\sqrt{15}\)
C) 8 \(\sqrt{15}\)
D) 10√5
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Correct option is (A) \(4\sqrt{15}\)
Given that roots of the equation \(12x^2+mx+5=0\) are real and equal.
\(\therefore m^2-4\times12\times5=0\)
\(\Rightarrow m^2=240\)
\(\Rightarrow m^2=16\times15\)
\(\Rightarrow m=\pm\sqrt{16\times15}\)
\(=\pm4\sqrt{15}\)
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