Starting with x0=1x_0 = 1x0=1, use the iteration formula xn+1=4xn2+5\displaystyle x_{n+1} = \frac{4}{x_n^2 + 5}xn+1=xn2+54 three times to find an estimate for the solution to x3+5x=4x^3 + 5x = 4x3+5x=4.
