so sánh:
a,\(3^{34}v\text{à5}^{20}\)
b,\(71^5v\text{à}17^{20}\)
So sánh:
a)\(2^{24}v\text{à}3^{16}\)
b)\(2^{300}v\text{à}3^{200}\)
c)\(71^5v\text{à}7^{20}\)
a) Ta có \(\hept{\begin{cases}2^{24}=\left(2^6\right)^4=64^4\\3^{16}=\left(3^4\right)^4=81^4\end{cases}}\)
Mà \(64< 81\)
\(\Rightarrow64^4< 81^4\)
\(\Rightarrow2^{24}< 3^{16}\)
b) Ta có \(\hept{\begin{cases}2^{300}=\left(2^3\right)^{100}=8^{100}\\3^{200}=\left(3^2\right)^{100}=9^{100}\end{cases}}\)
Mà 8 < 9
\(\Rightarrow8^{100}< 9^{100}\)
\(\Rightarrow2^{300}< 3^{200}\)
c) Ta có \(7^{20}=\left(7^4\right)^5=2401^5\)
Ta có 71 < 2401
\(\Rightarrow71^5< 2401^5\)
\(\Rightarrow71^5< 7^{20}\)
!! K chắc câu c
@@ Học tốt
Chiyuki Fujito
a) \(2^{24}=\left(2^3\right)^8=8^8\)
\(3^{16}=\left(3^2\right)^8=9^8\)
Ta thấy 8<9\(\Rightarrow8^8< 9^8\Rightarrow2^{24}< 3^{16}\)
b) \(2^{300}=\left(2^3\right)^{100}=8^{100}\)
\(3^{200}=\left(3^2\right)^{100}=9^{100}\)
Thấy \(8< 9\Rightarrow8^{100}< 9^{100}\Rightarrow2^{300}< 3^{200}\)
c) \(7^{20}=\left(7^4\right)^5=2401^5\)
Ta thấy \(71< 2401\Rightarrow71^5< 2401^5\Rightarrow71^5< 7^{20}\)
SO SÁNH:a) 3 mũ 34 và 5 mũ 20 b) 71 mũ 5 và 17 mũ 20
So sánh :
\(a,2^{30}v\text{à}3^{20}\)
\(b,5^{300}v\text{à}3^{500}\)
\(c,2^{24}v\text{à}3^{16}\)
\(d,\left(0,3\right)^{40}v\text{à}\left(0,1\right)^{20}\)
\(\text{a, }2^{30}=8^{10}\)
\(\text{ }3^{20}=\left(3^2\right)^{10}=9^{10}\)
\(\text{Vậy }2^{30}< 3^{20}\)
\(\text{b, }5^{300}=\left(5^3\right)^{100}=125^{100}\)
\(3^{500}=\left(3^5\right)^{100}=243^{100}\)
\(\text{Vậy }5^{300}< 243^{100}\)
\(\text{c, }2^{24}=\left(2^3\right)^8=8^8\)
\(3^{16}=\left(3^2\right)^8=9^8\)
\(\text{Vậy ...}\)
So sánh
\(a,2^{30}+3^{30}+4^{30}v\text{à}3^{20}+6^{20}+8^{20}\)
\(b,2^{30}+3^{30}+4^{30}v\text{à}3.24^{10}\)
\(c,2^0+2^1+2^2+...+2^{50}v\text{à}2^{51}\)
c) Đặt \(A=2^0+2^1+2^2+...+2^{50}\)
\(\Leftrightarrow2A=2^1+2^2+2^3...+2^{51}\)
\(\Leftrightarrow2A-A=2^1+2^2+2^3...+2^{51}\)\(-2^0-2^1-2^2-...-2^{50}\)
\(\Leftrightarrow A=2^{51}-2^0=2^{51}-1< 2^{51}\)
Vậy \(2^0+2^1+2^2+...+2^{50}< 2^{51}\)
a)Ta có: \(\hept{\begin{cases}2^{30}=\left(2^3\right)^{10}=8^{10}\\3^{30}=\left(3^3\right)^{10}=27^{10}\\4^{30}=\left(2^2\right)^{30}=2^{60}\end{cases}}\)và \(\hept{\begin{cases}3^{20}=\left(3^2\right)^{10}=9^{10}\\6^{20}=\left(6^2\right)^{10}=36^{10}\\8^{20}=\left(2^3\right)^{20}=2^{60}\end{cases}}\)
Mà \(8^{10}< 9^{10}\); \(27^{10}< 36^{10}\);\(2^{60}=2^{60}\)nên
\(8^{10}+27^{10}+2^{60}< 9^{10}+36^{10}+2^{60}\)
hay \(2^{30}+3^{30}+4^{30}< 3^{20}+6^{20}+8^{20}\)
b) Ta có: \(4^{30}=2^{30}.2^{30}=8^{10}.4^{15}\)
\(3.24^{10}=3.8^{10}.3^{10}=3^{11}.8^{10}\)
Vì \(4^{15}>3^{11}\) nên \(8^{10}.4^{15}>3^{11}.8^{10}\)
hay \(2^{30}+3^{30}+4^{30}>3.24^{10}\)
\(A=\frac{17^{20}+2}{17^{20}-1}v\text{à }B=\frac{17^{20}-2}{17^{20}-5}\)
\(A=\frac{17^{20}+2}{17^{20}-1}=\frac{17^{20}-1+3}{17^{20}-1}=1+\frac{3}{17^{20}-1}\)
\(B=\frac{17^{20}-2}{17^{20}-5}=\frac{17^{20}-5+3}{17^{20}-5}=1+\frac{3}{17^{20}-5}\)
Vì \(17^{20}-1>17^{20}-5\)
\(=>\frac{3}{17^{20}-1}1+\frac{3}{17^{20}-1}
\(A=\frac{20^{10}+1}{20^{10}-1}v\text{à}B=\frac{20^{10}-1}{20^{10}-3}Sos\text{á}nhAv\text{à}B\)
So sánh :
a , 334 và 520
b , 715 và 1720
3^34<8^34=2^3^24=2^72
5^20>8^20=2^3^20=2^60
Vì 2^72>2^60 nên 3^34>5^20
Câu b tự làm
a, 334 < 834 = ( 23 )34 = 2102
520 < 820 = ( 23 )20 = 260
Mà 2102 > 260 nên 334 > 520
b, 1720 = ( 174 )5 = 835215
Mà 715 < 835215 nên 715 < 1720
\(\frac{\text{2/36 - 1/15 - 2/153}}{\text{1/34 + 3/20 - 3/26 }}:\frac{\text{1 + 2/71 - 5/121}}{\text{65/121 - 26/71 - 13 }}\)
So sánh:
a)\(3^{200}v\text{à}2^{300}\)
b) \(71^{50}v\text{à}37^{75}\)
c) \(\frac{2016014}{2017015}v\text{à}\frac{2016016014}{2017017015}\)
a) 3200=(32)100=9100 ; 2300=(23)100=8100
=> 9100>8100 hay 3200>2300
b) 7150=(712)25=504125 ; 3775=(373)25=5065325
=> 504125<5065325 hay 7150<3775
c)rút gọn
2016014/2017015=2014/2015
2016016014/2017017015=2014/2015
=> 2014/2015 = 2014/2015