Tui không biết làm mấy nên nếu có sai thì bỏ qua nhá,mong không bị bc.Thanks..

`A = -5^{22} - {-222 - [-122 - (100 - 5^{22}) + 2022]}`

`A = -5^{22} - {-222 - [-122 - 100 + 5^{22} + 2022]}`

`A = -5^{22} - {-222 + 122 +100 - 5^{22} - 2022}`

`A = -5^{22} + 222 - 122 - 100 + 5^{22} + 2022`

`A = (5^{22} - 5^{22}) + (222 - 122 + 2022) - 100`

`A = 2122 - 100`

`A = 2022`

_________________________________________________

`B = 1 + 1/2 (1 + 2) + 1/3 (1 + 2 + 3) + ... + 1/20 (1 + 2 + 3 + ... + 20)`

`B = 1 + 1/2   . 2  . 3 : 2 +   1/3 . 3 . 4 + ... + 1/20 .  20 . 21 : 2`

`B = 2/2 + 3/2 + ... + 21/2`

`B= 115`

_________________________________________________

`C = (5.4^6. 9^4-3^9. (-8)^4)/(4.2^13. 3^8+2.8^4. (-27)^3)`

`C =(5.2^12. 3^8-3^9. 2^12)/(2^15. 3^8+2^13. 3^9. (-1)`

`C =(2^12. 3^8. (5-3))/(2^13. 3^8. (2^2-3.(-1)))`

`C =(2^13. 3^8)/(2^13. 3^8. 7)`

`C =1/7`