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प्रश्न
If the quadratic equation ax2 + bx + c = 0 has two real and equal roots, then 'c' is equal to ______.
विकल्प
`(-b)/(2a)`
`b/(2a)`
`(-b^2)/(4a)`
`b^2/(4a)`
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उत्तर
If the quadratic equation ax2 + bx + c = 0 has two real and equal roots, then 'c' is equal to `underlinebb(b^2/(4a))`.
Explanation:
If the quadratic equation ax2 + bx + c = 0 has two real and equal roots, then
b2 – 4ac = 0
`\implies` b2 = 4ac
`\implies` c = `b^2/(4a)`
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