Step 1 :Given the Taylor polynomial \(p_{2}(x)=1-x+\frac{x^{2}}{2}\), we need to substitute \(x=-0.04\) into this polynomial to approximate \(e^{-0.04}\).
Step 2 :Substitute \(x=-0.04\) into the polynomial to get \(p_{2} = 1.0408\).
Step 3 :Final Answer: The approximation of \(e^{-0.04}\) using the Taylor polynomial \(p_{2}(x)=1-x+\frac{x^{2}}{2}\) is \(\boxed{1.0408}\).