Question

If a,b are the roots of x²+2kx +k²-1=0 and a²+b²=10find k?

Answer 1

here a= 1 ,b= 2k ,c= k^2 -1
a^2 +b^2 = 10
1^2 + (2k)^2 = 10
1 + 4k^2 = 10
4k^2= 10 -1
k^2 = 9/4
k = √9/4
k= 3/2