1/6+1/7+1/8+1/9
=13/42+1/8+1/9
=73/168+1/9
=275/50444
\(\frac{1}{6}+\frac{1}{7}+\frac{1}{8}+\frac{1}{9}=\frac{84}{504}+\frac{72}{504}+\frac{63}{504}+\frac{56}{504}=\frac{84+72+63+56}{504}=\frac{275}{504}\)
1/6+1/7+1/8+1/9
=13/42+1/8+1/9
=73/168+1/9
=275/50444
\(\frac{1}{6}+\frac{1}{7}+\frac{1}{8}+\frac{1}{9}=\frac{84}{504}+\frac{72}{504}+\frac{63}{504}+\frac{56}{504}=\frac{84+72+63+56}{504}=\frac{275}{504}\)
1+1+1+1+1+2+3+4+5+6+7+8+9+10 x 1+1+1+1+1+2+3+4+5+6+7+8+9+10 +1+1+1+1+1+2+3+4+5+6+7+8+9+10 - 10 x 9 - 9 + 45 +46 +47 =
1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9+1+2+3+4+5+6+7+8+9=?
tinh nhanh 1/4*3+1/4*5+1/6*5+1/7*6+1/8*7+1/9*8+1/10*9=
1+1+1+2+2+2+3+3+3+4+4+4+5+5+5+6+6+6+7+7+7+8+8+8+9+9+9+.......+n
Tìm n
1/1×2 + 1/2×3 + 1/3×4 + 1/4×5 + 1/5×6 + 1/6×7 + 1/7×8 + 1/8×9 + 1/9×10
M.n ơi zúp mik với
Tính nhanh: A) 4/9+1/8+5/9+7/8 B) 1/6+4/6+5/12+7/6+7/12
Tính nhanh bằng cách rút gọn rồi tính:
a.(1/2+1/3+1/4+1/5+1/6+1/7+1/8+1/9)-(1/3+1/4+1/5+1/6+1/7+1/8+1/9+1/10)
b.(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)
Ai nhanh mình tick cho!
Tính nhanh :
1/10 + 2/9 +3/8 + 4/7 + 5/6 + 1/6 + 3/7 + 5/8 + 7/9 + 9/10
1+9+3+7+5+8+4+6+2+1+2+3+4+5+7+8+6+9=maays
67+9+1+9+1+9+3+1+4+7+7+7+7+8+9+3+6+2=dung minh tk