\(a,\frac{8^{2017}-8^{2015}}{8^{2014}.8}\)
\(=\frac{8^{2015}.\left(8^2-1\right)}{8^{2015}}\)
\(=64-1\)
\(=63\)
\(b,\frac{2^8+8^3}{2^5.2^3}\)
\(=\frac{2^8+\left(2^3\right)^3}{2^8}\)
\(=\frac{2^8+2^9}{2^8}\)
\(=\frac{2^8.\left(1+2\right)}{2^8}\)
\(=3\)
Học tốt
82017 - 82015 = 82015(82 - 1) = 82015.63
82014.8 = 82014+1 = 82015
=> \(\frac{8^{2017}-8^{2015}}{8^{2014}\cdot8}=\frac{8^{2015}\cdot63}{8^{2015}}=63\)
28 + 83 = 28 + (23)3 = 28 + 29 = 28(1 + 2) = 28.3
25.23 = 25+3 = 28
=> \(\frac{2^8+8^3}{2^5\cdot2^3}=\frac{2^8\cdot3}{2^8}=3\)
a)
\(=\left(8^{2017}-8^{2015}\right):\left(8^{2014}\cdot8\right)\)
\(=8^{2015}\left(8^2-1\right):8^{2015}\)
\(=8^{2015}\left(64-1\right):8^{2015}\cdot1\)
\(=8^{2015}\cdot\left(64-1-1\right)\)
\(=8^{2015}\cdot62\)
b)
\(=\left[2^8+\left(2^3\right)^3\right]:2^8\)
\(=\left[2^8+2^9\right]:2^8\)
\(=2^8\left(1+2^1\right):2^8\)
\(=3\)
Bài làm :
\(a\text{)}\frac{8^{2017}-8^{2015}}{8^{2014}.8}\)
\(=\frac{8^{2015}.\left(8^2-1\right)}{8^{2015}}\)
\(=8^2-1\)
\(=64-1\)
\(=63\)
\(b\text{)}\frac{2^8+8^3}{2^5.2^3}\)
\(=\frac{2^8+\left(2^3\right)^3}{2^8}\)
\(=\frac{2^8+2^9}{2^8}\)
\(=\frac{2^8.\left(1+2\right)}{2^8}\)
\(=1+2\)
\(=3\)
