(1-99/99)x(1-100/100)x.......x(1-2010/2010)=?
(17-100 + 83 ) x ( 1 + 3 + 5 + ........+99 ) + 2010
(100-1) x (100-2) x ... x (100-99) x(100-100)
( 100 - 1 ) x ( 100 - 2 ) x . . . x ( 100 - 99 ) x ( 100 - 100 )
tinh nhanh
[ 0 x 1 x 2 x 3 ...x 99 x 100] : [2 + 4 + 6 + ... 98]
[1+ 3 + 5 + 7 + ... 97 + 99 ] x [ 45 x 3 - 45 x 2 - 45]
132 x 145 + 100 /145 x 133 - 45
Tính nhanh
a,(1+2 +3 +...+99) x (13 x 15 – 12 x 15 –15)
b,2+4+ 6+...+ 98+100–(1+3 +5 +...+97+99)
Tính nhanh :
( 1 - 1/99 ) x ( 1- 1/100 ) x ... x ( 1- 2005 )
Tính:
(1-1/99)x(1-1/100)x(1-1/101)x....x(1-1/2016)
(x+1)+(x-2)+(x+3)+...+(x+99)+(x-100)=50