Giải giúp mình nhé:
1. ( 91-99+98)-(-99+98)
2. ( 99-98+97)-(99+97+98)
so sanh A=98/99
B=98*99+1/98*99
Tính \(T=\left(\frac{2}{98}+\frac{3}{97}+...+\frac{99}{1}\right)X\left(\frac{1}{99}+\frac{2}{98}+...+\frac{98}{2}\right)-\left(\frac{1}{99}+\frac{2}{98}+..+\frac{99}{1}\right)X\left(\frac{2}{98}+\frac{3}{97}+...+\frac{98}{2}\right)\)
(-99)+(98)+(-97)+...+97+98+99+100
1820 : [5.79 - (125+5.49) + 5.21]
(-99)+(-98)+(-97) +...+ 97+98+99+100
( -99) + (-98) + (-97) +....+97+98+99+100
( - 99 ) + ( - 98 ) + ( - 97 ) + ... + 97 + 98 + 99 + 100 = ?
tính hợp lý
(91 - 99 + 98) - (-99 + 98)