<p>You could do the vast majority of derivatives at a point without a calculator.</p>
<p>But for instance, if you didn’t remember the prodcut rule, the derivative of f(x) = sin(x)*2^x at x = pi could be calculated using the nDeriv function in the [MATH] menu on the TI-83 or TI-84 models. The syntax is:</p>
<p>nDeriv(sin(x)*2^x,x,pi)</p>
<p>This woudl give you the value of the derivative at x = pi.</p>