用Octave计算导数基本公式（15）

反三角函数求导公式（5）

\( ({\rm arcsec} x )'= \frac{1}{x^2 \cdot \sqrt{1-\frac{1}{x^2} } } \)

function [text_result, numeric_result] = func32()
    pkg load symbolic;
    x = sym('x');
    question = asec(x);
    lim = diff(question, x);
    text_result = ["\n", disp(lim)];
    numeric_result = eval(lim);
endfunction

>> [text_result, numeric_result] = func32()
text_result =
            1
    ────────────────
              ________
       2     ╱     1
      x ⋅   ╱  1 - ──
          ╱        2
        ╲╱        x

numeric_result = (sym)

            1
    ────────────────
             ________
       2     ╱     1
      x ⋅   ╱  1 - ──
          ╱        2
        ╲╱        x