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प्रश्न
Assertion (A): The roots of the quadratic equation 8x2 + 2x – 3 = 0 are `-1/2` and `3/4`.
Reason (R): The roots of the quadratic equation ax2 + bx + c = 0 are given by `x = (-b ± sqrt(b^2 - 4ac))/(2a)`
विकल्प
A is true, R is false
A is false, R is true
Both A and R are true
Both A and R are false
MCQ
अभिकथन और तर्क
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उत्तर
A is false, R is true
Explanation:
Use the quadratic formula from R:
`x = (-b ± sqrt(b^2 - 4ac))/(2a)`
This formula is correct.
For 8x2 + 2x – 3 = 0: a = 8, b = 2, c = –3.
Discriminant D = 22 – 4 × 8 × (–3)
= 4 + 96
= 100
`sqrt(D) = 10`
So, `x = (-2 ± 10)/16`
`x = 8/16`
`x = 1/2`
or
`x = -12/16`
`x = -3/4`
Assertion is wrong it stated `-1/2` and `3/4`, which are the signs swapped, so A is false while R is true.
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