## 6.8.18 TeX Instructions for Mathematical Formulas

          PROGRAM EXA6_2
          CHARACTER CSTR*80

          CALL SETPAG('DA4P')
          CALL DISINI
          CALL PAGERA
          CALL COMPLX
          CALL HEIGHT(40)

          CSTR='TeX Instructions for Mathematical Formulas'
          NL=NLMESS(CSTR)
          CALL MESSAG(CSTR, (2100 - nl)/2, 100)

          CALL TEXMOD('ON')
          CALL MESSAG('$\frac{1}{x+y}$', 150, 400)
          CALL MESSAG('$\frac{a^2 - b^2}{a+b} = a - b$', 1200, 400)

          CALL MESSAG('$r = \sqrt{x^2 + y^2}', 150, 700)
          CALL MESSAG('$\cos \phi = \frac{x}{\sqrt{x^2 + y^2}}$',
         *            1200, 700)

          CALL MESSAG('$\Gamma(x) = \int_0^\infty e^{-t}t^{x-1}dt$',
         *            150, 1000)
          CALL MESSAG('$\lim_{x \to \infty} (1 + \frac{1}{x})^x = e$',
         *            1200, 1000)

          CALL MESSAG('$\mu = \sum_{i=1}^n x_i p_i$', 150, 1300)
          CALL MESSAG('$\mu = \int_{-\infty}^ \infty x f(x) dx$',
         *            1200, 1300)

          CALL MESSAG('$\overline{x} = \frac{1}{n} \sum_{i=1}^n x_i$',
         *            150, 1600)
          CALL MESSAG('$s^2 = \frac{1}{n-1} \sum_{i=1}^n' //
         *            '(x_i - \overline{x})^2$', 1200, 1600)

          CALL MESSAG('$\sqrt[n]{\frac{x^n - y^n}{1 + u^{2n}}}$',
         *            150, 1900)
          CALL MESSAG('$\sqrt[3]{-q + \sqrt{q^2 + p^3}}$', 1200, 1900)

          CALL MESSAG('$\int \frac{dx}{1+x^2} = \arctan x + C$', 150, 2200)
          CALL MESSAG('$\int \frac{dx}{\sqrt{1+x^2}} = {\rm arsinh} x + C$',
         *            1200, 2200)

          CALL MESSAG('$\overline{P_1P_2} = \sqrt{(x_2-x_1)^2 + '//
         *            '(y_2-y_1)^2}$', 150,2500)
          CALL MESSAG('$x = \frac{x_1 + \lambda x_2}{1 + \lambda}$',
         *            1200, 2500)

          CALL DISFIN
          END

Figure 6.13: TeX Instructions for Mathematical Formulas