a) (-16).5  = -80          b) 30.(-8) = -240                c) 0.(-8)= 0

 d) 0:18 = 0               e) 0:(-13)= 0           f) (-10).8.(-6) =  480       g) 44:(-4)  = -11              i)-15.2.(-4).(-5) = -600

`a)(-16).5=-80`

`b)30.(-8)=-240`

`c)0.(-8)=0`

`d)0:18=0`

`e)0:(-13)=0`

`f)(-10).8.(-6)=(-80).(-6)=480`

`g)44:(-4)=-11`

`i)(-15).2.(-4).(-5)=[(-15).2].[(-4).(-5)]=(-30).20=-600`

`100^{3}:4^{3}=(4.25)^{3}:4^{3}=25^{3}.4^{3}:4^{3}=25^{3}=15625`

Trả lời

\(100^3:4^3=96^0=1\)

#Chucbanhoctot:)

( 2001 + 2002 - 2003 + 2004 ) + ( 2001 - 2002 - 2003 - 2004 )

= ( 2001 + 2004 - 1 ) + ( - 2002 - 2002 - 3 )

= 2001 - 2002 + 2004 - 2002 - 1 - 3 

= - 1 + 2 -1 -3 

= -2 + 2 - 3

= -3 

Số cặp số của tổng trên là : 

\(\left(50-1\right):1+1=50\) ( cặp ) 

Ta có : 

( y +1 ) + ( y + 2 ) + ( y + 3 ) + .... + ( y + 50 ) = 1425 

<=> 50y + 1 + 2 + 3 + ... + 50 = 1425

<=> 50y + \(\dfrac{\left(50+1\right).50}{2}\) =1425

<=>50y + 1275 = 1425 

<=> 50y = 150

<=> y = 3 

A= 1/30 + 1/42 + 1/56 + 1/72 + 1/90 + 1/110 + 1/132

A=1/5x6+1/6x7+1/7x8+1/8x9+1/9x10+1/10x11+1/11x12

A=1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10+1/10-1/11+1/11-1/12

A=1/5-1/12

A=... chắc vậy:V

\(=3\left(\dfrac{2}{3.5}+\dfrac{2}{5.7}+\dfrac{2}{7.9}+...+\dfrac{2}{99.101}\right)=\)

\(=3\left(\dfrac{5-3}{3.5}+\dfrac{7-5}{5.7}+\dfrac{9-7}{7.9}+...+\dfrac{101-99}{99.101}\right)=\)

\(=3\left(\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{9}+...+\dfrac{1}{99}-\dfrac{1}{101}\right)=\)

\(=3\left(\dfrac{1}{3}-\dfrac{1}{101}\right)=\dfrac{3.98}{101}\)