According to question ,
?. x2 ? 20x + 91= 0
? x2 ? 13x ? 7x + 91 = 0
? x(x ? 13) ? 7(x ? 13) = 0
? (x ? 7)(x ? 13) = 0
? x = 13, 7
?. y2 ? 32y + 247= 0
? y2 ? 19y ? 13y + 247 = 0
? y(y ? 19) ? 13(y ? 19) = 0
? (y ? 13)(y ? 19) = 0
? y = 13, 19
Hence, x ? y is required answer .
We can say that ,
The given quadratic equation x2 ? 6x + 5 = 0 ? ( x - 5 )( x - 1 ) = 0 ? x = 5 or 1
Now , | x - 3 | = 2 ? ( x - 3 ) = 2 or - ( x - 3 ) = 2 ? x = 3 + 2 = 5 or x = 3 - 2 = 1
? x2 - 6x + 5 = 0 and | x - 3 | = 2 are equivalent.
According to question , we have
The roots ?, ? of the equation : x2 ? 6x + k = 0
On comparing with ax2 + bx + c = 0 , we get a = 1 , b = - 6 , c = k
Now , ? + ? = ( - b/a ) = 6
? + ? = 6 and 3? + 2? = 20
On solving ,
? ? = 4, ? = 2
Product of the roots = k
So, k = ?? = 4 × 2 = 8.
Hence , required answer will be option A .
As per the given above question , we know that
Let, ?, ? be the roots of the equation x2 + kx + 12 = 0
? ? + ? = ?k and ?? = 12
Now ( ? - ? )2 = ( ? + ? )2 - 4??
( 1 )2 = k2 - 4(12)
? k2 = 49 ? k = ± 7.
find ? if ?2 + ?2 = |
|
|
Comments
There are no comments.Copyright ©CuriousTab. All rights reserved.