QQuestion
If 3 is a root of the quadratic equation x2 − px + 3 = 0, then p is equal to:
(a) 4
(b) 3
(c) 5
(d) 2
✓Answer
(a) 4
Explanation:
3 is a root of the quadratic equation x2 – px + 3 = 0
∴ 32 − 3p + 3 = 0
⇒ 9 − 3p + 3 = 0
⇒ 12 − 3p = 0
⇒ 3p = 12
Therefore, p = 4.
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