ax2+bx+c=0 (a≠0), a, b, c ∈R, has no real root and a+b+c<0, then
c≤0
c>0
c=0
c<0
The given equation is ax2+bx+c=0
Given that ax2+bx+c=0 has no real root,
f(x)=ax2+bx+c has same sign for all real x.
f(1)=a+b+c<0 (given)
⇒ f(0)=c<0