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The graph of the polynomial f(x) = ax2 + box + c is as shown in Fig. 2.20. Write the value of b2 – 4ac and the number of real zeros of f (x).
b2 – 4ac = 0, Two
The given quadratic equation touches the x-axis at only one point.
The root of the quadratic equation is equal and real because if the quadratic equation has two distinct roots, then the graph touches the x-axis at two points.
As we know that the roots are real and equal if the value of discriminant is zero,
So,
b2 – 4ac = 0