=(48/49) x (63/64) x (80/81) x (99/100) x (120/121) x (143/144)
=(6x8/7x7) x (7x9/8x8) x (8x10/9x9) x (9x11/10x10) x (10x12/11x11) x (11x13/12x12)
=\(\frac{6x8x8x10x10x12x7x9x9x11x11x13}{7x7x8x8x9x9x10x10x11x11x12x12}\)
rút gọn đi còn: 13/14
b,(1-1/49)x(1-1/64)x(1-1/81)x(1-1/100)x(1-1/121)x(1-1/144)
b,(1-1/49)x(1-1/64)x(1-1/81)x(1-1/100)x(1-1/121)x(1-1/144)
tính nhanh
b,(1-1/49)x(1-1/64)x(1-1/81)x(1-1/100)x(1-1/121)x(1-1/144)
tính nhanh
a,131313/151515+131313/353535+131313/636363+131313/999999
b,(1-1/49)x(1-1/64)x(1-1/81)x(1-1/100)x(1-1/121)x(1-1/144)
Gấp lắm rùi các bạn
Giúp nha rùi tick
[1-1/4]x[1-1/9]x[1-1/16]x.....x[1-1/100]x[1-1/121]
1) Tìm x
a) (1/4 x X - 1/8) x 3/4 = 1/4
b) 12/5 : X = 14/3 x 4/7
c) x + 2/3 = 8 : 4 - 1
2) Thực hiện phép tính:
a) (1/5 + 3/4) x 1/2
b) 13/20 - (1/4 - 5/20)
c) 1/10 + 4/20 + 9/30 + 25/50 + 36/60 + 49/70 + 64/80 + 81/90
d) 2/3.5 + 2/5.7 + 2/7.9 + ... + 2/41.43
( 1 - 1/4 ) x ( 1 - 1/9 ) x ( 1- 1/16 ) x ............ x (1 - 1/100 ) x ( 1 - 1/121 ) = ?
[ 1-1/4 ] x [1-1/9 ]x [ 1- 1/16 ] x..........x [ 1-1/100 ] x [ 1- 1/121 ]
( 1 - 1/4 ) x ( 1 - 1/9 ) x ( 1 - 1/16 ) x ... x (1 - 1/100) x (1- 1/121) = ?
