tim x biet 5^(2x-3)-2.5^2=5^2.3
Tim x
2.5^2.3^2+{[2.5^3-(5x+4).5]}:(262.3.5)}=453
tim x,biet:
5x=125 32x=81 52x-3 -2.52=52.3
5x=125
Mà: 53=125
=>x=3
32x=81
Mà: 34=81
=>32x=34
=>2x=4
=>x=4:2
=>x=2
52x-3-2.52=52.3
=>52x-3-50=75
=>52x-3=75+50
=>52x-3=125
Mà: 53=125
=> 52x-3=53
=>2x-3=3
=>2x=3+3
=>2x=6
=>x=6:2
=>x=3
5x=125
Mà: 53=125
=>x=3
32x=81
Mà: 34=81
=>32x=34
=>2x=4
=>x=4:2
=>x=2
52x-3-2.52=52.3
=>52x-3-50=75
=>52x-3=75+50
=>52x-3=125
Mà: 53=125
=> 52x-3=53
=>2x-3=3
=>2x=3+3
=>2x=6
=>x=6:2
=>x=3
5x=125
Mà: 53=125
=>x=3
32x=81
Mà: 34=81
=>32x=34
=>2x=4
=>x=4:2
=>x=2
52x-3-2.52=52.3
=>52x-3-50=75
=>52x-3=75+50
=>52x-3=125
Mà: 53=125
=> 52x-3=53
=>2x-3=3
=>2x=3+3
=>2x=6
=>x=6:2
=>x=3
Tim x:
3^2x-4 -x^0 = 8
65- 4^x+2 = 2014^0
120+2. ( 3x + 17) = 214
5^2x-3 - 2.5^2 = 5^2 = 5^2.3
30- [4(x-2)+15] =3
740:(x+10)= 10^2 - 2.13
[(6x-39):7].4= 12
*
\(3^2x-4-x^0=8\)
9x-4-1=8
9x-5=8
9x=13
=>x=\(\frac{13}{9}\)
trả lời nhanh giúp tôi
a)Chung minh: (54+55-2.54)chia het cho 20
b)tim x;y thuoc N,biet: (x-3)(2x-5)=7
5^2x-3-2.5^2=5^2.3
\(5^{2x-3}-2\cdot5^2=5^2\cdot3\)
\(\Rightarrow5^{2x-3}-50=75\)
\(\Rightarrow5^{2x-3}=75+50\)
\(\Rightarrow5^{2x-3}=125\)
\(\Rightarrow5^{2x-3}=5^3\)
\(\Rightarrow2x-3=3\)
\(\Rightarrow2x=6\)
\(\Rightarrow x=\dfrac{6}{2}=3\)
5^2x-3-2.5^2=5^2.3
\(5^{2x-3}-2.5^2=5^2.3\)
\(5^{2x-3}=2.5^2+5^2.3\)
\(2x-3=3\)
\(2x=3+3\)
\(2x=6\)
\(x=6:2=3\)
\(\Rightarrow x=3\)
a)5^x+1=125
b)5^2x-3-2.5^2=5^2.3
c)4^x.3=16
5^2x-3-2.5^2=5^2.3
25x-3-2.25=25.3
25x-3-50=75
25x-53=75
25x=75+53
25x=128
x=128
-----------
25
25x-3-2.25=25.3
25x-3-50=75
25x-53=75
25x=75+53
25x=128
x=128
-----------
25
\(5^{2x-3}-2.5^2=5^2.3\)
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