tìm x,y biết 5^2x-3-2:5^2=5^2.3
\(5^{2x-3}-2.5^2=5^2.3\)
Tìm số tự nhiên x , biết
\(5^{2x-3}-2.5^2=5^2.3\)
\(\Rightarrow5^{2x-3}=5^2.3+5^2.2\)
\(\Rightarrow5^{2x-3}=5^2.\left(2+3\right)=5^3\)
\(\Rightarrow2x-3=3\)
\(\Rightarrow2x=6\)
\(\Rightarrow x=3\)
\(5^{2x-3}\)-2.\(5^2\)= \(5^2\).3
\(5^{2x-3}\) _2.25=25.3
\(5^{2x-3_{ }}\)_50=75
\(5^{2x-3}\)= 75_50
\(5^{2x-3}\)= \(5^2\)
suy ra : 2x-3=2
2x=2.3
2x=6
x=6:2
x=3
Tìm x
(3^2-2^3)x+3^2.2^2=4^2.3
x^5-x^3=0
(x-1)^2+(-3)^2=5^2.(-1)^100
(2x-1)^2-(2x-1)=0
1.
$(3^2-2^3)x+3^2.2^2=4^2.3$
$\Leftrightarrow x+36=48$
$\Leftrightarrow x=48-36=12$
2.
$x^5-x^3=0$
$\Leftrightarrow x^3(x^2-1)=0$
$\Leftrightarrow x^3(x-1)(x+1)=0$
$\Leftrightarrow x^3=0$ hoặc $x-1=0$ hoặc $x+1=0$
$\Leftrightarrow x=0$ hoặc $x=\pm 1$
3.
$(x-1)^2+(-3)^2=5^2(-1)^{100}$
$\Leftrightarrow (x-1)^2+9=25$
$\Leftrightarrow (x-1)^2=25-9=16=4^2=(-4)^2$
$\Rightarrow x-1=4$ hoặc $x-1=-4$
$\Leftrightarrow x=5$ hoặc $x=-3$
4.
$(2x-1)^2-(2x-1)=0$
$\Leftrightarrow (2x-1)(2x-1-1)=0$
$\Leftrightarrow (2x-1)(2x-2)=0$
$\Leftrightarrow 2x-1=0$ hoặc $2x-2=0$
$\Leftrightarrow x=\frac{1}{2}$ hoặc $x=1$
$\Lef
`@` `\text {Ans}`
`\downarrow`
\((3^2-2^3)x+3^2.2^2=4^2.3\)
`=> x + (3*2)^2 = 48`
`=> x+6^2 = 48`
`=> x + 36 = 48`
`=> x = 48 - 36`
`=> x=12`
Vậy, `x=12`
\(x^5-x^3=0\)
`=> x^3(x^2 - 1)=0`
`=>`\(\left[{}\begin{matrix}x^3=0\\x^2-1=0\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=0\\x^2=1\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=0\\x=\pm1\end{matrix}\right.\)
Vậy, `x \in {0; +- 1 }`
\(\left(x-1\right)^2+\left(-3\right)^2=5^2\cdot\left(-1\right)^{100}\)
`=> (x-1)^2 + 9 = 25*1`
`=> (x-1)^2 + 9 = 25`
`=> (x-1)^2 = 25 - 9`
`=> (x-1)^2 = 16`
`=> (x-1)^2 = (+-4)^2`
`=>`\(\left[{}\begin{matrix}x-1=4\\x-1=-4\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=4+1\\x=-4+1\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=5\\x=-3\end{matrix}\right.\)
Vậy, `x \in {5; -3}`
\((2x-1)^2-(2x-1)=0\)
`=> (2x-1)(2x-1) - (2x-1)=0`
`=> (2x-1)(2x-1-1)=0`
`=>`\(\left[{}\begin{matrix}2x-1=0\\2x-2=0\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}2x=1\\2x=2\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=1\end{matrix}\right.\)
Vậy, `x \in {1; 1/2}`
1:Tìm x, biết:
a) (3/5)^2x-1 = 125/27
b)1/2+(1/2.3)+(1/3.4)+...+(1/2015.2016)-2x=1/2-1/2016
c)/2x^2+/x-2//=2x^2+3
Tìm x, biết:
a, (3/5)^2x-1=125/27
b,1/2+1/2.3+1/3.4+...+1/2015.2016 - 2x=1/2-1/2016
c,/2x^2+/x-2//=2x^2+3
Tìm số tự nhiên x:
e, 96-5(2x-1)=41
f, 2x^2-15=17
g,(3x-2)^2+15=64
h, 3(x+5)-2.3^2=21
i, 5^x+9=134.1^2010
Giúp mình zớii
e) 96-5(2x-1)=41
5(2x-1)= 96-41
5(2x-1)=55
2x-1=55:5
2x-1=11
2x=11+1
2x=12
x=12:2
x=6
Tìm x biết
a,|2x-1|=|x+2|
b,x+2/5=2-3x/3
c,2.3^x.3^2=18
b) x + 2/5 = 2-3x/3
x + 2/5 = 2 -x
x +x = 2 - 2/5
2x= 8/5
x = 8/5 x 1/2
x = 4/5
c) 2. 3^x . 3^2 = 18
3^x+2 = 18:2
3^ x+2 = 9
3^ x+2 = 3^2
=> x+2 = 2
=> x=0
a) TH1: 2x-1 = x + 2
2x-x = 2+1
x =3
TH2 : 2x-1 = -(x+2)
2x-1 = -x-2
2x +x = -2 +1
3x = -1
x = -1/3
Tìm x biết:
a,3/4.x+1/3=-1/2.
b,-x/4=-9/x.
c,/2x-1/=5.
d,3^2=81.
e,5^2-3 trừ 2.5^2=5^2.3.
Làm rồi mk tích cho.
mk chi lam duoc cau c thoi
suy ra 2x-1=5 hoac 2x-1=-5
2x=6 2x=-4
x=3 x=-2
vay x=3 hoac x=-2
a. 3/4.x+1/3=-1/2
=>3/4.x=-1/2-1/3=-5/6
=>x=-5/6 chia 3/4=-10/9
b. -x/4=-9/x =>-x*x=4*-9
=>-2x=-36 =>x=18
c./2x-1/=5
=> 2x-1=5 =>2x=5+1=6 =>x=3
hoặc 2x-1=-5 =>2x=-5+1=-4 =>x=-2
d,e: Sai đề rồi
Bài 4:tìm x
a.7x-x=5^21:5^19+3.2^2.7
b.11x-7x+3^4:3^3=5^4+2x
c.75-5.(x-3)^3=700
d.3.(2x-1)^2=75
e.3^x+3^x+2=270
f.3^x-3-3^2=2.3^2
Cảm ơn các bản !
a, 7\(x\) - \(x\) = 521 : 519 + 3.22.7
6\(x\) = 53 + 3.4.7
6\(x\) = 125 + 12.7
6\(x\) = 125 + 84
6\(x\) = 209
\(x\) = 209 : 6
\(x\) = \(\dfrac{209}{6}\)
b; 11\(x\) - 7\(x\) + 34 : 33 = 54 + 2\(x\)
4\(x\) + 3 = 625 + 2\(x\)
4\(x\) - 2\(x\) = 625 - 3
2\(x\) = 622
\(x\) = 622 : 2
\(x\) = 311
c; 75 - 5.(\(x-3\))3 = 700
5.(\(x\) - 3)3 = 700 - 75
5.(\(x\) - 3)3 = - 625
(\(x\) - 30)3 = - 625 : 5
(\(x\) - 30)3 = - 125
(\(x-3\))3 = (-5)3
\(x\) - 3 = - 5
\(x\) = - 5 + 3
\(x\) = -2
d, 3.(2\(x\) - 1)2 = 75
(2\(x\) - 1)2 = 75 : 3
(2\(x\) - 1)2 = 25
\(\left[{}\begin{matrix}2x-1=-5\\2x-1=5\end{matrix}\right.\)
\(\left[{}\begin{matrix}2x=-5+1\\2x=5+1\end{matrix}\right.\)
\(\left[{}\begin{matrix}2x=-4\\2x=6\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=-2\\x=3\end{matrix}\right.\)
d) \(3.\left(2x-1\right)^2=75\)
\(\left(2x-1\right)^2=75\div3\)
\(\left(2x-1\right)^2=25\)
\(\left(2x-1\right)^2=5^2\)
\(\Rightarrow2x-1=5\)
\(2x=5+1\)
\(2x=6\)
\(x=6\div2\)
\(x=3\)