Show that the equation 3x + 2 cos x + 5 = 0 has exactly one real root. Find the smallest possible area of an isosceles triangle that is circumscribed about a circle of radius r. Use the graphs of f, f', and f" to estimate the x-coordinates of the maximum and minimum points and inflection points of f. cos X 41. f (x) = - VX2 + X + 1' -TEXT 42. f (X) = e-01x In(x? - 1)