tìm x biết
5^x+5^x+2=625
Tìm x biết :
\(5^x.\left(5^3\right)^2=625\)
5x.(53)2=625
=> 5x.56=54
=> 5x=54:56
=> 5x=5-2
=> x=-2
Vậy x=-2
\(^{=>5^x.5^6=5^4}\)
=> \(5^x=5^{4-6}\)
=>x=-2
Tìm x biết : 5x . ( 53 )2 = 625
5^x.5^6=5^4
5^x=5^4:5^6
5^x= tap hop rong
Suy ra x= tap hop rong
\(5^x.\left(5^3\right)^2=625\)
\(5^x.5^6=5^4\)
\(5^x=5^4\text{ }:\text{ }5^6\)
\(5^x=5^{-2}\)
\(\Rightarrow\text{ }x=-2\)
Tìm x biết:
5x . (53)2 = 625
5x . ( 53 )2 = 625
<=> 5x . 56 = 625
<=> 5x+6 = 625
<=> 5x+6 = 54
<=> x + 6 = 4
<=> x = -2
\(5^x.\left(5^3\right)^2=625\)
\(\Leftrightarrow5^x.5^6=625\)
\(\Leftrightarrow5^x=\frac{1}{5^2}\)
\(\Leftrightarrow x=-2\)
\(5^x\times\left(5^3\right)^2=625\)
\(\Rightarrow5^x\times5^6=625\)
\(5^{x+6}=5^4\)
\(\Rightarrow x+6=4\)
\(x=-2\)
Vậy x = -2
Tìm x biết
(7.x + 1) : 2 - 23 = 2
(625:x + 4) .29 -80= 41
[ (4.x + 5) : 7 + 5 ] .2 + 16 = 20
(7.x + 1) : 2 - 23 = 2
=> (7.x + 1) : 2 = 2 + 23
=> (7.x + 1) : 2 = 25
=> 7.x + 1 = 25 . 2
=> 7.x + 1 = 50
=> 7.x = 50 - 1
=> 7.x = 49
=> x = 49 : 7 = 7
(7.x + 1) : 2 - 23 = 2
=> (7.x + 1) : 2 = 2 + 23
=> 7.x + 1 = 25 . 2
=> 7.x = 50 - 1
=> 7.x = 49
x = 49 : 7 = 7
Vậy.............
hok tốt
Tìm x , biết :
x5 = 625 . x
5x+2 + 5x+1+ 5x = 19375
x^5=625.x
<=>x^5:x=625
<=>x^4=625
<=>x^4=5^4
<=>x=5
Tìm x biết 5x . 5x+1= 625
5x . 5x+1= 625
5x+x+1= 625
5x+x+1=54
=>x+x+1=4
2x+1=4
2x=4-1
2x=3
x=3:2
x=1,5
1.tìm x biết
a) x-(-1/4)=-5/6+1/8
b) 5^x+2=625
c) -22/15.x+1/3=|-2/3+1/5|
Tìm x biết:
\(25^{x+1}.125^x.625^{x+2}=\left(5^2\right)^5\)giúp mik nhé!cảm ơn nhiều lắm
Ta có: 25x + 1 . 125x . 625x + 2 = (52)5
=> (52)x + 1 . (53)x . (54)x+ 1 = 510
=> 52x + 2 . 53x . 54x + 8 = 510
=> 2x + 2 + 3x + 4x + 8 = 10
=> 9x + 2 + 8 = 10
=> 9x = 10 - 2 - 8
=> 9x = 0
=> x = 0 : 9
=> x = 0
Tìm x biết:
a,(2x+3/5)^2-9/25=0
b,(3x-1).(-1/2x+5)=0
c, (7/5)^x+1-(1/5)^x=-4/625
d,(2/3)^x+2+(2/3)^x+1=20/27
a) \(\left(2x+\frac{3}{5}\right)^2-\frac{9}{25}=0\)
\(\left(2x+\frac{3}{5}\right)^2=\frac{9}{25}\)
\(\left(2x+\frac{3}{5}\right)^2=\left(\frac{3}{5}\right)^2\)
\(=>2x+\frac{3}{5}=\frac{3}{5}\)
\(2x=\frac{3}{5}-\frac{3}{5}\)
\(2x=0\)
\(x=0:2\)
\(x=0\)
b) \(\left(3x-1\right).\left(-\frac{1}{2x}+5\right)=0\)
=> \(\left(3x-1\right)=0\)hoặc \(\left(-\frac{1}{2x}+5\right)=0\)hoặc \(\left(3x-1\right)\)và\(\left(-\frac{1}{2x}+5\right)\)cùng bằng 0.
\(\orbr{\begin{cases}3x-1=0\\-\frac{1}{2x}+5=0\end{cases}}=>\orbr{\begin{cases}3x=1\\-\frac{1}{2x}=-5\end{cases}}=>\orbr{\begin{cases}x\in\varnothing\\2x=\frac{1}{5}\end{cases}}=>x=\frac{1}{5}:2=>x=\frac{1}{10}\)
a) \(\left(2x+\frac{3}{5}\right)^2-\frac{9}{25}=0\)
\(\left(2x+\frac{3}{5}\right)^2=0+\frac{9}{25}\)
\(\left(2x+\frac{3}{5}\right)^2=\frac{9}{25}\)
\(\left(2x+\frac{3}{5}\right)^2=\left(\frac{3}{5}\right)^2\)
\(\orbr{\begin{cases}2x+\frac{3}{5}=\frac{3}{5}\\2x+\frac{3}{5}=-\frac{3}{5}\end{cases}}\)
\(\orbr{\begin{cases}x=0\\x=-\frac{3}{5}\end{cases}}\)
b) \(\left(3x-1\right)\left(-\frac{1}{2}x+5\right)=0\)
\(\left(3x-1\right)\left(-\frac{x}{2}+5\right)=0\)
\(\left(3x-1\right)\left(5-\frac{x}{2}\right)=0\)
\(\orbr{\begin{cases}3x-1=0\\5-\frac{x}{2}=0\end{cases}}\)
\(\orbr{\begin{cases}x=\frac{1}{3}\\x=10\end{cases}}\)