1, Tìm X
a) 2x3X = 162
b) 2X - 15 = 17
c)(7X - 11)3 = 25 x 52 + 200
tìm x biết
( 7x - 11 ) 3 = 25 . 52 + 200
X=0
Vì 2 mũ 5 = 32
2 mũ 2 = 4
Suy ra 2 mũ 5 + 2 mũ 2 +200 = 32+4+200=236
* ước của 236 = (1;2;4;59;118;236)
* Mà chỉ có 59+11=70 có chữ số đầu tiên là 7
ĐÚNG THÌ TICK CHO MÌNH NHA
1.
a) 2x + 5 = 34 : 32
b) ( 3x - 24 ) . 73 = 2.74
c) [ 3 . ( 42 - x ) + 15 = 23 . 3
d) 126 + ( 132 - x ) = 300
2.
a) 120 - ( x + 55 ) = 60
b) ( 7x - 11)3 = 25 .52 + 200
c) 2x + 2x+4 = 544
3.
a) 10 + 2x = 49 : 47
b) 70 - 5 ( x - 3 ) = 45
c) 4 + 95 : x = 143 : 142 - 23
1)
a) 2x + 5 = 3⁴ : 3²
2x + 5 = 3²
2x + 5 = 9
2x = 9 - 5
2x = 4
x = 4 : 2
x = 2
b) (3x - 24).73 = 2.74
(3x - 24).73 = 148
3x - 24 = 148/73
3x = 148/73 + 24
3x = 1900/73
x = 1900/73 : 3
x = 1900/219
c) [3.(42 - x)] + 15 = 23.3
126 - 3x + 15 = 69
141 - 3x = 69
3x = 141 - 69
3x = 72
x = 72 : 3
x = 24
d) 126 + (132 - x) = 300
132 - x = 300 - 126
132 - x = 174
x = 132 - 174
x = -42
2)
a) 120 - (x + 55) = 60
x + 55 = 120 - 60
x + 155 = 60
x = 60 - 55
x = 5
b) (7x - 11).3 = 25.52 + 200
(7x - 11).3 = 1500
7x - 11 = 1500 : 3
7x - 11 = 500
7x = 500 + 11
7x = 511
x = 511 : 7
x = 73
c) 2x + 2x + 4 = 544
4x = 544 - 4
4x = 540
x = 540 : 4
x = 135
3)
a) 10 + 2x = 49 : 47
10 + 2x = 49/47
2x = 49/47 - 10
2x = -421/47
x = -421/47 : 2
x = -421/94
b) 70 - 5(x - 3) = 45
5(x - 3) = 70 - 45
5(x - 3) = 25
x - 3 = 25 : 5
x - 3 = 5
x = 5 + 3
x = 8
c) 4 + 95 : x = 143 : 142 - 23
4 + 95 : x = -3123/142
95 : x = -3123/142 - 4
95 : x = -3691/142
x = 95 : (-3691/142)
x = -13490/3691
(7x-11)3=25 x 52+200
(7x - 11)3 = 25.52 + 200
<=> (7x - 11)3 = 32.25 + 200
<=> (7x - 11)3 = 800 + 200
<=> (7x - 11)3 = 1000
<=> (7x - 11)3 = 103
<=> 7x - 11 = 10
<=> 7x = 21
<=> x = 3
tìm x ;
a) 2x - 15 = 17
b) ( 7x - 11 )3 = 25 : 52 = 200
ai nhanh like
2x-15=17
2x=17+15
2x=32
x=32:2
x=16
(7x - 11)3= 25 . 52 + 200 . 20230
\(\left(7x-11\right)^3=2^5\cdot5^2+200\cdot2023^0\\ \left(7x-11\right)^3=32\cdot25+200\cdot1\\ \left(7x-11\right)^3=1000\\ \left(7x-11\right)^3=10^3\\ 7x-11=10\\ 7x=21\\ x=\dfrac{21}{7}=3\)
Lời giải:
$(7x-11)^3=2^5.5^2+200.2023^0=32.25+200=1000=10^3$
$\Rightarrow 7x-11=10$
$\Rightarrow 7x=21$
$\Rightarrow x=3$
TÌM X
(7x-11)^3=2^5.5^2+200
x^10=x
(2x-15)^5=(2x-15)^3
b) x^10=1x
=> x=0 ; 1
c)(2x-15)^5=(2x-15)^3
=> (2x-15)^4 = (2x-15)^2
=> (2x-15)^2 =1
=> 2x-15=1
=> x=8
Tìm x ∈ N biết:
a) 2 x - 15 = 17
b) ( 7 x - 11 ) 3 = 2 5 . 5 2 + 200
Tìm x
1) (7x - 11)x = 25.52+200
2) (2x - 15)5 = (2x - 15)3
thì cứ tính bên phải trước rồi tìm x như thường thôi
Tìm x
720 : [41-(2x-5)] =2^3 . 5
2^x = 15 = 17
(7x-11)^3= 2^5.5^2+200
720 : [41-(2x-5)] =2^3 . 5
<=> 41-(2x-5)=720:40=18
<=> 2x-5=41-18=23
<=>2x=23+5=28
<=> x=28:2=14
2^x-15=17
<=> 2^x=17+15=32
<=> 2^x=2^5
<=> x=5
(7x-11)^3= 2^5.5^2+200
<=> (7x-11)^3=1000
<=> (7x-11)^3=10^3
<=> 7x-11=10
<=> 7x=10+11=21
<=> x=21:7=3
Tìm x thuộc N biết:
a, (7x - 11)3 = 25 . 52 + 200
b, (2x - 15)5 = (2x - 15)3