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Question
If the equation ax2 + 2x + a = 0 has two distinct roots, if
Options
a = ±1
a = 0
a = 0, 1
a = −1, 0
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Solution
a = ±1
Explanation:
If the roots of given equation are distinct then
d = b2 – 4ac = 0
⇒ d = b2 – 4ac = 0
⇒ 22 – 4(a) (a) = 0
⇒ 4 – 4a2 = 0
⇒ 4a2 = 4
⇒ a2 = 1
⇒ a = ±1
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