b) Ta có: \(9^5=\left(3^2\right)^5=3^{10}\)
\(27^3=\left(3^3\right)^3=3^9\)
Vì 10 > 9 => 310 > 39
Vậy 95 > 273
1. So sánh :
b) 9^5 và 27^3
9^5 = ( 3^2 )^5 = 3^10
27^3 = ( 3^3 )^3 = 3^9
Vì 3^10 > 3^9 => 9^5 > 27^3
Vậy 9^5 > 27^3
c) \(\left(\frac{1}{8}\right)^6\)và \(\left(\frac{1}{32}\right)^4\)
\(\left(\frac{1}{8}\right)^6=\left(\frac{1}{2}\right)^{3.6}=\left(\frac{1}{2}\right)^{18}\)
\(\left(\frac{1}{32}\right)^4=\left(\frac{1}{2}\right)^{5.4}=\left(\frac{1}{2}\right)^{20}\)
Vì ( 1/2)^18 < (1/2)^20 => (1/8)^6 < (1/32)^4
Vậy (1/8)^6 < (1/32)^4
a) ta có \(\hept{\begin{cases}\left(-2\right)^{14}=\left(-2^7\right)^2=128^2\\5^6=5^{3.2}=\left(5^3\right)^2=125^2\end{cases}}\)
vì \(128>125\Rightarrow128^2>125^2\Rightarrow5^6< \left(-2\right)^{14}\)
vậy \(5^6< \left(-2\right)^{14}\)
b) ta có \(\hept{\begin{cases}27^3=\left(3^3\right)^3=3^9\\9^5=\left(3^2\right)^5=3^{10}\end{cases}}\)
vì \(3^{10}>3^9\Rightarrow9^5>27^3\)
vậy \(9^5>27^3\)
c) ta có \(\hept{\begin{cases}\left(\frac{1}{8}\right)^6=\left(\frac{1}{2}\right)^{18}\\\left(\frac{1}{32}\right)^4=\left(\frac{1}{2}\right)^{20}\end{cases}}\)
vì \(18< 20\Rightarrow\left(\frac{1}{2}\right)^{18}< \left(\frac{1}{2}\right)^{20}\Rightarrow\left(\frac{1}{8}\right)^6< \left(\frac{1}{32}\right)^4\)
vậy \(\left(\frac{1}{8}\right)^6< \left(\frac{1}{32}\right)^4\)
Nguyễn bá lương: \(\left(-2^7\right)=-128\)