Question

bài 2: so sánh

a)\(\left(\frac{1}{2}\right)^{225}va\left(\frac{1}{3}\right)^{100}\)

 giải nhanh giúp mk với nhé mk tick cho

Answer 1

Ta có

\(\left(\frac{1}{2}\right)^{225}\)=\(\left(\frac{1}{2}\right)^{9.25}\)=\(\left(\frac{1}{512}\right)^{25}\)

\(\left(\frac{1}{3}\right)^{100}\)=\(\left(\frac{1}{3}\right)^{4.25}\)=\(\left(\frac{1}{81}\right)^{25}\)

Vì \(\frac{1}{512}\)<\(\frac{1}{81}\)   => \(\left(\frac{1}{512}\right)^{25}\)<\(\left(\frac{1}{81}\right)^{25}\)

Hay  \(\left(\frac{1}{2}\right)^{225}\)<\(\left(\frac{1}{3}\right)^{100}\)

Mong bạn tích cho mình nhé

 

Answer 2

\(\left(\frac{1}{2}\right)^{225}=\left[\left(\frac{1}{2}\right)^9\right]^{25}=\left(\frac{1}{81}\right)^{25}\)\(\left(\frac{1}{2}\right)^{225}=\left[\left(\frac{1}{2}\right)^9\right]^{25}=\left(\frac{1}{81}\right)^{25}\)

\(\left(\frac{1}{3}\right)^{100}=\left[\left(\frac{1}{3}\right)^4\right]^{25}=\left(\frac{1}{81}\right)^{25}\) 

vì   \(\left(\frac{1}{81}\right)^{25}=\left(\frac{1}{81}\right)^{25}\Rightarrow\left(\frac{1}{2}\right)^{225}=\left(\frac{1}{3}\right)^{100}\)

\(\Rightarrowđpcm\)