OLULI 20Es.ICBSE Sept.2012)33. a, b are the roots of the quadratic pol

1.	OLULI 20Es.ICBSE Sept.2012)33. a, b are the roots of the quadratic polynomial p(x) = x2 - (k-6)x + (2k + 1). Find the value ofk, if a + B = aß.[CBSE Sept. 2010, 2012]
Answer» Given:α , β are roots of x²-(k-6)x+2k+1 Also α + β=α βHere a=1;b=-(k-6);c=2k+1 sum of roots=α + β=-b/a=-(-(k-6))=k-6 product of roots =αβ=c/a=2k+1 now k-6=2k+12k-k=-6-1k=-7 Thus k=-7

OLULI 20Es.ICBSE Sept.2012)33. a, b are the roots of the quadratic polynomial p(x) = x2 - (k-6)x + (2k + 1). Find the value ofk, if a + B = aß.[CBSE Sept. 2010, 2012]

Answer»

Given:α , β are roots of x²-(k-6)x+2k+1

Also α + β=α βHere a=1;b=-(k-6);c=2k+1

sum of roots=α + β=-b/a=-(-(k-6))=k-6

product of roots =αβ=c/a=2k+1

now k-6=2k+12k-k=-6-1k=-7

Thus k=-7