Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a: =>3x-15-2x+6=51
=>x-9=51
=>x=60
b: =>432-2x+22+3x-15=200
=>x+439=200
=>x=-239
c: =>3x+17-4x+13=0
=>30-x=0
=>x=30
d: =>x-3-3x+6=-11-21=-32
=>-2x+3=-32
=>-2x=-35
=>x=35/2
\(3\cdot\left(x-5\right)-2\cdot\left(x-3\right)=51\)
\(\Rightarrow3x-15-2x+6=51\)
\(\Rightarrow x-9=51\)
\(\Rightarrow x=51+9\)
\(\Rightarrow x=60\)
b) \(432-2\cdot\left(x-11\right)+3\cdot\left(x-5\right)=200\)
\(\Rightarrow432-2x+22+3x-15=200\)
\(\Rightarrow x+439=200\)
\(\Rightarrow x=200-439\)
\(\Rightarrow x=-239\)
c) \(3x+17=4x-13\)
\(\Rightarrow4x-3x=17+13\)
\(\Rightarrow x=30\)
d) \(\left(x-3\right)+21=3\cdot\left(x-2\right)-11\)
\(\Rightarrow x-3+21=3x-6-11\)
\(\Rightarrow x+18=3x-17\)
\(\Rightarrow3x-x=18+17\)
\(\Rightarrow2x=35\)
\(\Rightarrow x=\dfrac{35}{2}\)
\(1+2+3+...+x=500500\)
\(\Rightarrow\frac{x.\left(x+1\right)}{2}=500500\)
\(\Rightarrow x.\left(x+1\right)=1001000\)
\(\Rightarrow1000.1001\)
..
(x + 5)3 . 2 = 432
(x + 5)3 = 432 : 2
(x + 5)3 = 216
x + 5 = \(\sqrt[3]{216}\)
x + 5 = 6
x = 6 - 5
x = 1
***
x3 + 52 . 32 = 252
x3 + 25 . 9 = 252
x3 + 225 = 252
x3 = 252 - 225
x3 = 27
x3 = \(\sqrt[3]{27}\)
x = 3
a) (x + 5)3.2 = 432
=> (x + 5)3 = 432 : 2
=> (x + 5)3 = 216 = 63
=> x + 5 = 6
=> x = 6 - 5
=> x = 1
b) x3 + 52.32 = 252
=> x3 + 25.9 = 252
=> x3 + 225 = 252
=> x3 = 252 - 225
=> x3 = 27 = 33
=> x = 3
\(70-5\cdot\left(x-3\right)=45\)
\(\Rightarrow5\cdot\left(x-3\right)=70-45\)
\(\Rightarrow5\cdot\left(x-3\right)=25\)
\(\Rightarrow x-3=\dfrac{25}{5}\)
\(\Rightarrow x-3=5\)
\(\Rightarrow x=5+3=8\)
==============
\(10+2\cdot x=4^5:4^3\)
\(\Rightarrow10+2\cdot x=4^2\)
\(\Rightarrow10+2\cdot x=16\)
\(\Rightarrow2\cdot x=16-10\)
\(\Rightarrow2\cdot x=6\)
\(\Rightarrow x=\dfrac{6}{2}=3\)
=============
\(2\cdot x-138=2^3\cdot3^2\)
\(\Rightarrow2\cdot x-138=72\)
\(\Rightarrow2\cdot x=72+138\)
\(\Rightarrow2\cdot x=210\)
\(\Rightarrow x=\dfrac{210}{2}=105\)
==============
\(231-\left(x-6\right)=1339:12\)
\(\Rightarrow231-x+6=1339:12\)
\(\Rightarrow237-x=\dfrac{1339}{12}\)
\(\Rightarrow x=237-\dfrac{1339}{12}\)
\(\Rightarrow x=\dfrac{1505}{12}\)
\(3^{x-1}=432:4^2=27=3^3\)
\(\Rightarrow x-1=3\Leftrightarrow x=4\)
a) \(15+2^n=31\)
\(2^n=16\Rightarrow n=4\)
b) \(2.2^n+4.2^n=6.2^5\)
\(2^n\left(2+4\right)=6.2^5\)
\(2^n.6=6.2^5\Rightarrow n=5\)
c) \(32^n:16^n=1024\)
\(\left(2^5\right)^n:\left(2^4\right)^n=2^{10}\)
\(2^{5n}:2^{4n}=2^{10}\)
\(2^n=2^{10}\Rightarrow n=10\)
d) \(5^n+5^{n+2}=650\)
\(5^n+5^n.25=650\)
\(5^n\left(1+25\right)=650\)
\(5^n.26=650\)
\(5^n=25\Rightarrow n=2\)
e) \(3^n+5.3^{n+1}=432\)
\(3^n+5.3^n.3=432\)
\(3^n\left(1+15\right)=432\)
\(3^n.16=432\)
\(3^n=27\Rightarrow n=3\)
TL:
33 . 2n = 432
33 . 2n = 24 . 33
\(\Rightarrow\) 2n = 24
n = 4
Vậy n = 4
HT
@@@@@
=> 27 x 2^n = 432
=> 2^n = 16
=> 2^n = 2^4
=> n = 4
Chúc em học tốt nha:3