Giúp mình với, mình cần gấp!
Tìm X :(1/2) ^ x=1/64
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1) \(\dfrac{1}{27}+a^3=\left(\dfrac{1}{3}+a\right)\left(\dfrac{1}{9}-\dfrac{a}{3}+a^2\right)\)
2) \(=\left(2x+3y\right)\left(4x^2-6xy+9y^2\right)\)
3) \(=\left(\dfrac{1}{2}x+2y\right)\left(\dfrac{1}{4}x-xy+4y^2\right)\)
4) \(=\left(x^2+1\right)\left(x^4-x^2+1\right)\)
5) \(=\left(x^3+1\right)\left(x^6-x^3+1\right)\)
6) \(=\left(x-4\right)\left(x^2+4x+16\right)\)
7) \(=\left(x-5\right)\left(x^2+5x+25\right)\)
8) \(=\left(2x^2-3y\right)\left(4x^4+6x^2y+9y^2\right)\)
9) \(=\left(\dfrac{1}{4}x^2-5y\right)\left(\dfrac{1}{16}x^4+\dfrac{5}{4}x^2y+25y^2\right)\)
10) \(=\left(\dfrac{1}{2}x-2\right)\left(\dfrac{1}{4}x^2+x+4\right)\)
11) \(=\left(x+2\right)^3\)
12) \(=\left(x+3\right)^3\)
\(\dfrac{1}{2}\) \(\times\) ( \(x\) - \(\dfrac{2}{3}\)) - \(\dfrac{1}{3}\) \(\times\) ( 2\(x\) - 3) = \(x\)
\(\dfrac{1}{2}\) \(\times\) \(\dfrac{3x-2}{3}\) - \(\dfrac{2x-3}{3}\) = \(x\)
\(\dfrac{3x-2}{6}\) - \(\dfrac{4x-6}{6}\) = \(\dfrac{6x}{6}\)
3\(x-2-4x\) + 6 = 6\(x\)
-\(x\) + 4 - 6\(x\) = 0
7\(x\) = 4
\(x\) = \(\dfrac{4}{7}\)
64 : 2x+5 + 11 = 12
64 : 2x+5 = 1
2x+5 = 64 = 26
=> x + 5 = 6
x = 1
a)\(x^{23}=64.x^{20}\)
\(\Leftrightarrow\frac{x^{23}}{x^{20}}=64\)
\(\Leftrightarrow x^3=64\Rightarrow x=4\)
b)\(\left(4x-3\right)^4=3-4x\)
\(\Leftrightarrow\left(3-4x\right)^4=3-4x\)
\(\Leftrightarrow\left(3-4x\right)^3=1\)
\(\Leftrightarrow3-4x=1\)
\(\Leftrightarrow x=\frac{1}{2}\)
`#3107.101107`
`|3x - 1| = x + 2`
`\Rightarrow` TH1: `3x - 1 = x + 2`
`\Rightarrow 3x - x = 2 + 1`
`\Rightarrow 2x = 3`
`\Rightarrow x =` $\dfrac{3}2$
TH2: `3x - 1 = -(x + 2)`
`\Rightarrow 3x - 1 = -x - 2`
`\Rightarrow 3x + x = -2 + 1`
`\Rightarrow 4x = -1`
`\Rightarrow x =` $\dfrac{-1}4$
Vậy, \(x\in\left\{-\dfrac{1}{4};\dfrac{3}{2}\right\}.\)
|3x - 1| = x + 2
*) TH1: x ≥ 1/3, ta có:
|3x - 1| = x + 2
3x + 1 = x + 2
3x - x = 2 - 1
2x = 1
x = 1/2 (nhận)
*) TH2: x < 1/3, ta có:
|3x - 1| = x + 1
1 - 3x = x + 1
-3x - x = 1 - 1
-4x = 0
x = 0 (nhận)
Vậy x = 0; x = 1/2
x=6 nha!
\(\left(\frac{1}{2}\right)^x=\frac{1}{64}\)
\(\left(\frac{1}{2}\right)^x=\left(\frac{1}{2}\right)^6\)
=> x=6