Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(a,x+21=6\\ \Rightarrow x=-15\\ b,x-10=-8\\ \Rightarrow x=2\\ c,\left(-8\right)x=\left(-7\right)\left(-6\right)\\ \Rightarrow\left(-8\right)x=42\\ \Rightarrow x=-4\\ d,20+8\left(x+3\right)=5^2.4\\ \Rightarrow20+8\left(x+3\right)=25.4\\ \Rightarrow20+8\left(x+3\right)=100\\ \Rightarrow8\left(x+3\right)=80\\ \Rightarrow x+3=10\\ \Rightarrow x=7\)
\(a.x+21=6\\ x=6-21\\ x=-15\\ b.x-10=-8\\ x=-8+10\\ x=2\\ c.-8x=-7.\left(-6\right)-2\\ -8x=42-2\\ -8x=40\\ x=40:\left(-8\right)\\ x=-5\)
\(d.20+8\left(x+3\right)=5^2.4\\ 20+8x+24=25.4\\ 44+8x=100\\ 8x=100-44\\ 8x=56\\ x=56:8\\ x=7\)
\(\text{(x+2)(y-3)=5 }\)
\(\Rightarrow\)x+2;y-3\(\in\)Ư(5)
Mà Ư(5)={1;5;-1;-5}
Có bảng:
Th1:
x+2=1;y-3=6
=>x=-3
y=9
Tương tự 3 trường hợp còn lại
a, \(\frac{3}{8}=\frac{6}{x}\Rightarrow3x=6.8\Rightarrow3x=48\Rightarrow x=\frac{48}{3}=16\)
b, \(\frac{1}{8}=\frac{x}{27}\Rightarrow8x=27\Rightarrow x=\frac{27}{8}\)
c, \(\frac{4}{x}=\frac{6}{8}\Rightarrow6x=4.8\Rightarrow6x=32\Rightarrow x=\frac{32}{6}=\frac{16}{3}\)
d, \(\frac{x}{6}=\frac{5}{24}\Rightarrow24x=30\Rightarrow x=\frac{30}{24}=\frac{5}{4}\)
Sửa đề
\(\left(x-2\right)^6=\left(x-2\right)^8\)
\(\Rightarrow\left(x-2\right)^6-\left(x-2\right)^8=0\)
\(\Rightarrow\left(x-2\right)^6\left[1-\left(x-2\right)^2\right]=0\)
\(\Leftrightarrow\orbr{\begin{cases}\left(x-2\right)^6=0\\1-\left(x-2\right)^2=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x-2=0\\\left(x-2\right)^2=1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=0+2\\\left(x-2\right)^2=\left(\pm1\right)^2\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=2\\x-2=1\\x-2=-1\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=2\\x=3\\x=1\end{cases}}\)
P/s : 2 dòng cuối bn chuyển \(\hept{\begin{cases}\\\\\end{cases}}\)thành \(\orbr{\begin{cases}\\\end{cases}}\)
-2.(x-6)+6.(x-10)=8.(-7)
-2x-(-2).6+6x-6.10=-56
-2x+2.6+6x+(-6).10=-56
-2x+6x+12+(-60) =-56
x.(-2+6)+12+(-60) =-56
4x+12+(-60) =-56
4x+12 =-56-(-60)
4x+12 =4
4x =4-12
4x =-8
x =-8:4
x =-2
(x-6)^6=(x-6)^8
=>(x-6)^6-(x-6)^8=0
=>[(x-6)^6]*1-(x-6)^6*(x-6)^2=0
=>(x-6)^6*[1-(x-6)^2]=0
=>[(x-6)^6=0 =>[x-6=0 =>[x=0+6 =>[x=6
[1-(x-6)^2=0 [(x-6)^2=1-0 [(x-6)^2=1 [(x-6)^2=(+-1)^6
=>[x=6 =>[x=6
[x-6=1 hoac x-6=-1 [x=1+6=7 hoac x=-1+6=5
Vay x={5,6,7} tiiiiiiiiiiiiiiiiiiiiiiiiiiiicccccccccccccckkkkkkkkkkkkkkkkkk
x=6 hoặc x=7
\(\left(x-6\right)^6=\left(x-6\right)^8\)
\(\Leftrightarrow\left(x-6\right)^6.\left(x-5\right).\left(x-7\right)\)
\(\Leftrightarrow\hept{\begin{cases}x-6=0\\x-5=0\\x-7=0\end{cases}}\Leftrightarrow\hept{\begin{cases}x=6\\x=5\\x=7\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x=6\\x=5\\x=7\end{cases}}\)