- 10 + ( - 999 )
= - ( 999 - 10 )
= - 989
- 10 + ( - 999 )
= - ( 999 - 10 )
= - 989
Tinh tong :
A = 9 + 99 + 999 +........+ 999 999 999 999
Cac ban lam on giup mink voi
Mink se k cho ban nao lam nhanh , dung , chi tiet nhat .
Thank you !
Tinh tong :
1-4+7-10+...+307-310+313
Cac ban giup minh nha(kem loi giai)
f.1+3+5+7+......+999
m.3+7+11+15+......+99
cac ban giup minh voi nha.
hihi tinh tong giup mk nha
s2 =10+12+14+...+2010
lam dung mk tich cho
Tinh tong: a) 9 + 99 + 999 + ... + 999...999 ( co 10 c/s 9 )
b) Tim x, biet: 1/21 + 1/28 = 1/36 +... + 2/x(x+1) = 2 / 9
A=1+2+3+...+999 tinh tong
B=10+12+14+...+2014 tinh tong
mn giup minh nha
tinh nhanh
a, 35.34+35.86+65.75+65.45
b, 10+11+12+13+........+ 99
c,(1+3+5+7+....+2017).(135135.137 + 135.137137)
cam cac ban da giup minh
GIUP MK CAU NAY VS
a. Tim chu so a va so tu nhien x sao cho (12 +3x)2 = 1a96
b. Tinh gia tri bieu thuc : S= 9+99+999+9999+....+99..99(2017 so 9)
giup mik giai phep tinh nay 2x+3x=5
chieu mik di hoc roi giup mik nha