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  1. If α, β are the roots of the equation 2x2 - 3x + 1 = 0, form an
    equation whose roots are
    α
    and
    β
    β
    α
    1. 2x2 + 5x + 2 = 0
    2. 2x2 - 5x - 2 = 0
    3. 2x2 - 5x + 2 = 0
    4. None of these
Correct Option: C

As we know that ,
∴ α, β are the roots of the equation 2x2 - 3x + 1 = 0

∴ α + β =
3
........... ( 1 )
2

and αβ =
1
........... ( 2 )
2

We are to form a quadratic equation whose roots are
α
and
β
β
α

S = sum of the roots =
α
+
β
=
α 2 + β 2
=
( α + β ) 2 - 2αβ
βααβαβ

S =
3
2 - 2
1
22
1
2
∴ Using ( 1 ) and ( 2 ) , we get
S =
9
- 1
4
1
2

S =
5
x
2
=
5
4
1
2

P = Product of the roots =
α
×
β
= 1
β
α

Hence the required quadratic equation is x2 − (sum of the roots)x + (Product of the roots) = 0
⇒ x2 -
5
x + 1 = 0
2

⇒ 2x2 - 5x + 2 = 0.



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