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प्रश्न
If one of the roots of quadratic equation x2 – kx – 15 = 0 is – 3, then find the value of ‘k’
उत्तर
– 3 is one of the roots of the equation x2 – kx – 15 = 0.
Putting x = – 3 in the given equation, we get
(– 3)2 – k(– 3) – 15 = 0
∴ 9 + 3k – 15 = 0
∴ 3k – 6 = 0
∴ 3k = 6
∴ k = `6/3`
∴ k = 2
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