Question

So sánh \(\left(\frac{1}{80}\right)^7\) với \(\left(\frac{1}{243}\right)^6\)

Answer 1

\(\left(\frac{1}{80}\right)^7>\left(\frac{1}{81}\right)^7=\left(\frac{1}{3^4}\right)^7>\left(\frac{1}{3^5}\right)^6=\left(\frac{1}{243}\right)^6\)

Answer 2

 

\(\left(\frac{1}{80}\right)^7>\left(\frac{1}{81}\right)^7=\left(\frac{1}{3^4}\right)^7=\frac{1^7}{\left(3^4\right)^7}=\frac{1}{3^{28}}\)

\(\left(\frac{1}{243}\right)^6=\left(\frac{1}{3^5}\right)^6=\frac{1^6}{\left(3^5\right)^6}=\frac{1}{3^{30}}\)

Vì \(\frac{1}{3^{28}}>\frac{1}{3^{30}}\) nên \(\left(\frac{1}{80}\right)^7>\left(\frac{1}{243}\right)^6\)

 

 

Answer 3

ta có

=243^6

=(3^5)^6=3^30>3^28

=(3^4)^7

=81^7>80^... 
=>(1/80)^7>(1/243)^6