Bài 1:
`((2^6 . 5 . 7).(5^4 . 7^9))/((2.5.7^2)^5)`
`= (2^6 . 5 . 7. 5^4 . 7^9)/(2^5 . 5^5 . 7^10)`
`= (2^6 . 5^4 . 7^10)/(2^5 . 5^5 . 7^10)`
`= (2.1.1)/(1 . 5 .1)`
`= 2/5`
Bài 2:
`a) -37 + 54 + (-70)+ (-163) + 246`
`= [-37+(-163)] + (54 + 246) + (-70)`
`= (-200) + 300 + (-70)`
`= 30`
`b) -359 +181 + ( - 123) +350 + (-172 )`
`= -178 + ( - 123) +350 + (-172 )`
`= [-178 + (-172 )] + ( - 123) +350`
`= -350 + ( - 123) +350`
`= (-350 + 350) + (-123)`
`= 0 + (-123)`
`= -123`
`c) 1+2-3-4+5+6-7-8+9+10-11-12 +…- 299-300+301+302`
`= 1 + (2-3-4+5) + (6-7-8+9) + (10-11-12 +13)+...+(298-299-300+301) + 302`
`= 1 + 0 + 0 + 0+....+0 + 302`
`= 303`
(Chúc bạn học tốt)