Đáp án+Giải thích các bước giải:
`(5^2 .6^5 +12^3 .15^2)/(2.6^5 .10^3 -81^2 .20^2)`
`=(5^2 .3^5 .2^5 +3^3 . 2^6 .3^2 .5^2)/(2. 2^5 .3^5 . 5^3 .2^3 -3^8 .5^2 .2^4`
`=(5^2 .3^5 .2^5+3^5 .5^2 .2^6)/(2^9 .3^5 .5^3 -3^8 .5^2 .2^4)`
`=(2^5 .3^5 .5^2(1+2))/(2^4 .5^2 .3^5(2^5 .5 -3^3))`
`=(2.3)/(32.5-27)`
`=6/133`