運算式 4: "s" Subscript, 1 , Baseline equals 1 half cosine left parenthesis, 2 pi "f" Subscript, "m" , Baseline "x" negative 2 pi "f" Subscript, "c" , Baseline "x" , right parenthesis 有圖檔。 要進行圖形閱讀，請按 Alt + T 鍵。s1=12cos2πfmx−2πfcx
4
運算式 5: "s" Subscript, 2 , Baseline equals negative 1 half cosine left parenthesis, 2 pi "f" Subscript, "m" , Baseline "x" positive 2 pi "f" Subscript, "c" , Baseline "x" , right parenthesis 有圖檔。 要進行圖形閱讀，請按 Alt + T 鍵。s2=−12cos2πfmx+2πfcx
5
運算式 6: "s" Subscript, 1 , Baseline plus "s" Subscript, 2 , Baseline 有圖檔。 要進行圖形閱讀，請按 Alt + T 鍵。s1+s2
