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The value of a for which both the roots of the equation 1 - a 2 x 2 + 2 a x - 1 = 0 lie between 0 and 1, will always be greater than 
MathematicsQuadratic EquationJEE Main
Solution:
1102 Upvotes Verified Answer
The correct answer is: 2
Given equation is 1 - a 2 x 2 + 2 a x - 1 = 0

Its discriminant D=4 and roots are 1 a - 1 , 1 a + 1

Given,   0 < 1 a - 1 < 1 ,  0 < 1 a + 1 < 1

Now,  1 a - 1 > 0   a > 1 ,

1 a - 1 < 1    ⇒   1  a - 1 - 1 < 0

⇒    2 - a a - 1 < 0   a < or  a > 2

∴  a > 2                                       .... (1)

 and   1 a+1 >0a>1

and  1 a + 1 < 1 - a a + 1 < 0

     a < - 1   or  a > 0

∴  a>0                ... (2)

From (1) and (2),    a > 2

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