摘要：基础 分解 $$ \begin{align*} f_e(t)&=\frac12[f(t)+f(-t)]\ f_o(t)&=\frac12[f(t)-f(-t)]\ f_r(t)&=\frac12[f(t)+f^(t)]\ \mathrm jf_i(t)&=\frac12[f(t)-f^(t)] \e 阅读全文