Some equations for testing TeX function:

(1) <math>\phi = \frac{1}{1 + \frac{1}{1 + \frac{1}{1 + \frac{1}{1 + ...}}}}</math>

(2) <math>\phi = \frac{1}{1 + \phi}</math>

(3) <math>\phi + \phi^2 = 1</math>

(4) <math>\phi^2 + \phi - 1 = 0</math>

(5) <math>\phi = \frac{1 \plusmn \sqrt{5}}{2}</math>

(6) <math>\phi \approx 1.61804, -0.61804 </math>