Đáp án: `=\frac{-5}{8}`
Giải thích các bước giải:
`\frac{8^5 .(-5)^8 +(-2)^5 .10^9}{2^{16} .5^7 +20^8}`
`=\frac{(2^3)^5 .5^8 -2^5 .(2.5)^9}{2^{16} .5^7 +(2^2 .5)^8}`
`=\frac{2^{15} .5^8 -2^5 .2^9 .5^9}{2^{16} .5^7 +2^{16} .5^8}`
`=\frac{2^{15} .5^8 -2^{14} .5^9}{2^{16} .5^7 +2^{16} .5^8}`
`=\frac{2^{14} .5^8 . (2-5)}{2^{16} .5^7 .(1+5)}`
`=\frac{2^{14} .5^8 . (-3)}{2^{16} .5^7 .6}`
`=\frac{2^{14} .5^8 . (-3)}{2^{17} .5^7 .3}`
`=\frac{-5}{2^3}=\frac{-5}{8}`
