Let y=f(x) be a parabola of the form y=x2+ax+1 such that no point of the parabola is below x−axis. If its tangent at the point of intersection with y−axis also touches the circle x2+y2=r2, then the slope of the tangent when radius of the circle is maximum is

Let y=f(x) be a parabola of the form y=x2+ax+1 such that no point of t

1.	Let y=f(x) be a parabola of the form y=x2+ax+1 such that no point of the parabola is below x−axis. If its tangent at the point of intersection with y−axis also touches the circle x2+y2=r2, then the slope of the tangent when radius of the circle is maximum is
Answer» Let $y = f (x)$ be a parabola of the form $y = x^{2} + a x + 1$ such that no point of the parabola is below $x -$ axis. If its tangent at the point of intersection with $y -$ axis also touches the circle $x^{2} + y^{2} = r^{2}$ , then the slope of the tangent when radius of the circle is maximum is