5/8 - 2/5 =?
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
mình đang cần gấp câu trả lời ,bạn nào giải được nhanh k luôn ,hứa đấy
![](https://rs.olm.vn/images/avt/0.png?1311)
Lời giải chi tiết:
8 – 3 = 5 | 8 – 5 = 3 | 8 – 6 = 2 | 8 – 8 = 0 |
8 – 1 – 2 = 5 | 8 – 2 – 3 = 3 | 8 – 5 – 1 = 2 | 8 – 0 = 8 |
8 – 2 – 1 = 5 | 8 – 3 – 2 = 3 | 8 – 1 – 5 = 2 | 8 + 0 = 8 |
![](https://rs.olm.vn/images/avt/0.png?1311)
a,
\(5^{x+4}-3.5^{x+3}=2.5^{11}\)
\(\Rightarrow5^{x+3}\left(5-3\right)=2.5^{11}\)
\(\Rightarrow5^{x+3}2=2.5^{11}\)
\(\Rightarrow5^{x+3}=5^{11}\)
\(\Rightarrow x+3=11\)
\(\Rightarrow x=8\)
b, (Check lai xem de sai o dau khong nhe)
\(3.5^{x+2}+4.5^{x+3}=19.5^{10}\)
Dat 5x ra ben ngoai
\(\Rightarrow5^x.5^23+5^x:5^{-3}.4\)
\(\Rightarrow5^x\left(5^2.3+5^{-3}.4\right)\)
\(\Rightarrow5^x\left(5^{-3}.5^5.3+5^{-3}.4\right)\)
\(\Rightarrow5^x[5^{-3}\left(5^53+4\right)\)
\(\Rightarrow5^x[5^{-3}\left(3125.3+4\right)\)
\(\Rightarrow5^x\left(5^{-3}\right).9379\)
=> Khong tim duoc gia tri cua x \(\Rightarrow x\in\varnothing\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(=\dfrac{2^{10}\cdot2\cdot5\cdot5^6+5^{10}\cdot2^8}{2^8\cdot5^4+5^7\cdot2^5}\)
\(=\dfrac{2^8\cdot5^7\left(2^3+5^3\right)}{2^5\cdot5^4\left(2^3+5^3\right)}=2^3\cdot5^3=10^3=1000\)
\(\left(4^5.10.5^6+25^5.2^8\right):\left(2^8.5^4+5^7.2^5\right)\)
\(=\dfrac{\left(2^2\right)^5.5.2.5^6+\left(5^2\right)^5.2^8}{2^8.5^4+5^7.2^5}\)
\(=\dfrac{2^{11}.5^7+5^{10}.2^8}{2^8.5^4+5^7.2^5}\)
\(=\dfrac{2^8.5^7\left(2^3+5^3\right)}{2^5.5^4\left(2^3+5^3\right)}\)
\(=2^3.5^3=\left(2.5\right)^3\)
\(=10^3=1000\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{2^8.5^4+2^7.5^3}{2^7.5^5-2^8.5^4}=\frac{2^7.5^3\left(2.5+1\right)}{2^7.5^4\left(5-2\right)}=\frac{2^7.5^3.11}{2^7.5^4.3}=\frac{5^3.11}{5^3.5.3}=\frac{11}{5.3}=\frac{11}{15}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
9/40 nha
5/8 - 2/5 = 25/40 - 16/40 = 9/40 nhé