Find the value of k such that 3x2+2kx+x−k−5 has the sum of zeros as half of their products.
Let P(x)=3x2+2kx+x−k−5
=3x2+x(2k+1)−(k+5)
i.e; ax2+bx+c
a=3;b=2k+1;c=−(k+5)
1) Sum of zeroes = −ba=−(2k+1)3
2) Product of zeroes = ca=−(k+5)3
According to given
−(2k+1)/3=12[−(k+5)/3]
2(2k+1)=k+5
4k+2=k+5
3k=3⇒k=1