化简 (8!)/(7!(8-7)!)

解答

化简

\frac{8 !}{7 ! ( 8 - 7 ) !}

8

求解步骤

\frac{8 !}{7 ! ( 8 - 7 ) !}

数字相减:

8 - 7 = 1

= \frac{8 !}{7 ! \cdot 1 !}

消去因子:

\frac{n !}{( n - m ) !} = n \cdot (n - 1) \dots (n - m + 1), n > m

\frac{8 !}{7 !} = 8

= \frac{8}{1 !}

\frac{8}{1 !} = 8

= 8

∣ 5 - 3 x ∣ = 3

s im pl i f y (\frac{- 2 x}{1 - x ^{2}})^{2}

s im pl i f y \frac{2 π}{120 π}

- 27 = 2 x^{2} + 3 x

f a c t or 81 m^{4} - 1