Question #1cabf

1 Answer
Oct 8, 2017

a) k216k+60
b) k=6,10
c) as in explanation

Explanation:

a) in ax2+bx+c=0(b24ac)(k8)241(8k+1)=k216k+60
b)b24ac=0=>two equal roots=>k216k+60=0(k6)(k10)=0k=6 or k=10
c) when b24ac<0,f(x) is always more than 0
so if k=8,b24ac=4<0, and f(x)>0 always (when a>0)