NoteSchoolM2二項式定理!!!: 階乘6!=6×5×4×3×2×1=7206! = 6 \times 5 \times 4 \times 3 \times 2 \times 1 = 7206!=6×5×4×3×2×1=720(a+b)n=∑r=0nCrnan−rbr(a+b)^n=\sum_{r=0}^{n} C^n_ra^{n-r}b^r(a+b)n=r=0∑nCrnan−rbrLast updated on December 27, 2025續三角函數