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प्रश्न
If the coefficient of x2 and the constant term of a quadratic equation have opposite signs, then the quadratic equation has real roots.
पर्याय
True
False
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उत्तर
This statement is True.
Explanation:
Because in this case discriminant is always positive.
For example, in ax2+ bx + c = 0, as a and c have opposite sign, ac < 0
⇒ Discriminant = b2 – 4ac > 0
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Solution :
Compare x2 + 2x – 9 = 0 with ax2 + bx + c = 0
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