 class="arithmatex">\(Z(x, x_0, c, A) := c+ x_0 + \bb{A}(x-x_0)\)</span>.</p>
<p>This leads to the following six derivative (tangent) function <span class="arithmatex">\(F_\alpha(x)\)</span>:</p>
<ul>
<li>
<p><em>x-location</em>: <span class="arithmatex">\(\alpha = c_1\)</span> and <span class="arithmatex">\(F_\alpha = F_x(z) = \frac{\partial F(z)}{\partial x}\)</span></p>
</li>
<li>
<p><em>y-location</em>: <span class="arithmatex">\(\alpha = c_2\)</span> and <span class="arithmatex">\(F_\alpha = F_y(z) = \