



 
Hi Pranav, Let $f(x) = a x^2 + b x  5$ and notice that $f(0) = 5.$ Think of the graph of $y = f(x).$ Since $f(x) = 0$ has no real roots the graph does not cross the Xaxis. But at $x = 0$ the point on the graph is below the Xaxis so the entire graph is below the Xaxis. What is $f(1)?$ Penny  


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