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If α and β are the roots of the equation x2 - 3λx + λ2 = 0,
find λ if α2 + β2 = 7 4
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± 1 2 -
± √7 2 -
± √3 2 - None of these
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Correct Option: A
Given that :- α, β are the roots of the equation x2 - 3λx + λ2 = 0
α + β = 3λ ....................( 1 )
and αβ = λ2 ...................( 2 )
Now, α2 + β2 = | ( given ) | |
⇒ ( α + β )2 - 2αβ = | |
⇒ ( 3λ)2 - 2λ2 = | |
⇒ 7λ2 = | |
⇒ λ2 = | |
⇒ λ = ± | . | |
Hence , required answer will be option A .