Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
vậy hông
\(\frac{2^2}{2^{x+y}}=8\)và \(\frac{3^2.\left(x+y\right)}{3^{5y}}=343\)
\(\left(\dfrac{3}{4}+\dfrac{2}{3}\right):\dfrac{17}{4}-\dfrac{3}{4}\)
\(=\left(\dfrac{9}{12}+\dfrac{8}{12}\right):\dfrac{17}{4}-\dfrac{3}{4}\)
\(=\dfrac{17}{12}:\dfrac{17}{4}-\dfrac{3}{4}\)
\(=\dfrac{17.4}{17.12}-\dfrac{3}{4}\)
\(=\dfrac{1}{3}-\dfrac{3}{4}\)
\(=\dfrac{4}{12}-\dfrac{9}{12}\)
\(=-\dfrac{5}{12}\)
b) \(\left|x+3\right|+3=3\)
\(\Rightarrow\left|x+3\right|=3-3\)
\(\Rightarrow\left|x+3\right|=0\)
\(\Rightarrow x+3=0\)
\(\Rightarrow x=0-3\)
\(\Rightarrow x=-3\)
Vậy \(x=-3.\)
c) \(\left|x-1\right|-1,7=5,7\)
\(\Rightarrow\left|x-1\right|=5,7+1,7\)
\(\Rightarrow\left|x-1\right|=7,4\)
\(\Rightarrow\left[{}\begin{matrix}x-1=7,4\\x-1=-7,4\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=7,4+1\\x=\left(-7,4\right)+1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=8,4\\x=-6,4\end{matrix}\right.\)
Vậy \(x\in\left\{8,4;-6,4\right\}.\)
d) \(2^{100}\) và \(10^{30}.\)
Ta có:
\(2^{100}=\left(2^{10}\right)^{10}=1024^{10}.\)
\(10^{30}=\left(10^3\right)^{10}=1000^{10}.\)
Vì \(1024>1000\) nên \(1024^{10}>1000^{10}.\)
\(\Rightarrow2^{100}>10^{30}.\)
Chúc bạn học tốt!
\(x+\left(\dfrac{2}{5}\right)^2=\dfrac{9}{10}\)
=>\(x+\dfrac{4}{25}=\dfrac{9}{10}\)
=>\(x=\dfrac{9}{10}-\dfrac{4}{25}=\dfrac{45}{50}-\dfrac{8}{50}=\dfrac{37}{50}\)
`x + (2/5)^2 = 9/10`
`=> x + 4/25 = 9/10`
`=> x = 9/10 - 4/25`
`=> x = 45/50 - 8/50`
`=> x = 37/50`
-------------------------
`(x+2/5)^2 = 9/10`
`=> (x+2/5)^2 = (3/sqrt{10})^2`
`=> x + 2/5 = 3/sqrt{10}` hoặc `x + 2/5 = -3/sqrt{10}`
`=> x = 3/sqrt{10} - 2/5` hoặc `x = -3/sqrt{10} - 2/5`
`=> x = (-4+3sqrt{10})/10` hoặc `x = -(4+3sqrt{10})/10`