<p>I understand that tools are becoming more sophisticated these days.But, do engineers use calculus equations on their jobs?</p>
<p>As always, the answer is ‘it depends’. I (being an ECE in radar control systems) perform differentiation occasionally (as in daily for a while, then months without it). Some engineers use it a lot. My H (ChemE - process engineer) has actually forgotten how to compute a derivative! I use differential equations, but usually ones that were solved long ago. Linear algebra and probability theory I use constantly.</p>
<p>What about PDEs specifically and Complex Analysis?</p>
<p>A lot of times you are using it but you do not know. Tabulated values or software output comes from calculus but you do not have to do the calculation each time.</p>
<p>Statistics is actually more generally useful in industry. But calculus has its functions and should not be neglected.</p>