5^x = 125 tìm x
Tìm x 5^x.5^3=125
\(5^x\cdot5^3=125\)
\(\Rightarrow5^x\cdot5^3=5^3\)
\(\Rightarrow5^{x+3}=5^3\)
\(\Rightarrow x+3=3\)
\(\Rightarrow x=3-3\)
\(\Rightarrow x=0\)
Vậy: x = 0
Tìm x : ( 5^2.x - 5^x+1) :5=125
\(\dfrac{125}{5^x}=5\)
tìm x biết
`125/5^x=5`
`-> 125/5^x=5/1`
`-> 5*5^x=125`
`->`\(5^{1+x}=125\)
`->`\(5^{1+x}=5^3\)
`->`\(x+1=3\)
`-> x=3-1`
`-> x=2`
Vậy, `5^x=5^2`.
Tìm x: (x+5)+(x+10)+...+(x+25)-125=150
\(\left(x+5\right)+\left(x+10\right)+...+\left(x+25\right)-125=150\)
\(\Leftrightarrow x+5+x+10+...+x+25-125=150\)
\(\Leftrightarrow5x-50=150\)
\(\Leftrightarrow5x=100\)
\(\Leftrightarrow x=\dfrac{100}{5}=20\)
Vậy \(x=20\)
Bài kia mik làm sai r
\(\left(x+5\right)+\left(x+10\right)+...+\left(x+25\right)-125=150\)
\(\Leftrightarrow x+5+x+10+...+x+25-125=150\)
\(\Leftrightarrow5x-50=150\)
\(\Leftrightarrow5x=200\)
\(\Leftrightarrow x=\dfrac{200}{5}=40\)
Vậy \(x=40\)
Tìm X, 125:X+75:X=5
125 : x + 75 : x = 5
(125 + 75) : x = 5
200 : x = 5
x = 200 : 5
x = 40
125 : x + 75 : x = 5
(125 + 75) : x = 5
200 : x = 5
x = 200 : 5
x = 40
tìm x thuộc Z biết x/5=125/x
Có : \(\dfrac{x}{5}=\dfrac{125}{x}\)
\(\Leftrightarrow x^2=5.125\)
\(\Leftrightarrow x=\pm25\)
Có : \(\dfrac{x}{5}=\dfrac{125}{x}\)
\(\Leftrightarrow x^2=5.125\)
\(\Leftrightarrow x=\pm25\)
Tìm x
x3+125+(x+5)(x-25)=0
\(x^3\) + 125 + (\(x\) + 5)(\(x\) - 25) = 0
(\(x^3\) + 53) + (\(x\) + 5)(\(x\) - 25) = 0
(\(x\) + 5)(\(x^2\) - 5\(x\) + 25) + (\(x\) + 5)(\(x\) - 25) =0
(\(x\) + 5)(\(x^2\) - 5\(x\) + 25 + \(x\) - 25) = 0
(\(x\) + 5)(\(x^2\) - 4\(x\)) = 0
\(x\)(\(x\) + 5)(\(x\) - 4) = 0
\(\left[{}\begin{matrix}x=0\\x+5=0\\x-4=0\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=0\\x=-5\\x=4\end{matrix}\right.\)
`x^3 + 125 + (x + 5)(x - 25) = 0`
`<=>(x + 5)(x^2 + 5x + 25) + (x + 5)(x - 25) = 0`
`<=>(x + 5)(x^2 + 6x) = 0`
`<=>x(x + 5)(x + 6) = 0`
`<=>x = 0` hoặc `x = -5` hoặc `x=-6`
Sửa:
`x^3 + 125 + (x + 5)(x - 25) = 0`
`<=>(x + 5)(x^2 - 5x + 25) + (x + 5)(x - 25) = 0`
`<=>(x+5)(x^2-4x)=0`
`<=>x(x+5)(x-4)=0`
`<=>x=0` hoặc `x=-5` hoặc `x=4`
Tìm XX biết: (X \times 5 - 19) + (X \times 3 + 24) = 125.(X×5−19)+(X×3+24)=125. \Trả lời: X =X=
Tìm X biết: (X x 5 - 19) + (X x 3 + 24) = 125
=>5x-19+3x+24=125
=>8x+5=125
hay x=15
Tìm X biết: (X x 5 - 19) + (X x 3 + 24) = 125
( 5 x − 19 ) + ( 3 x + 24 ) = 125
. 5 x − 19 + 3 x + 24 = 125
8 x + 5 = 125
8 x = 120
x = 15