\(\Leftrightarrow\dfrac{1}{2^{x+1}}=\dfrac{1}{8}\)
=>x+1=3
hay x=2
Đúng 0
Bình luận (0)
Ôn tập toán 7
Các câu hỏi tương tự
Tìm x ϵ Z
\(\left(\frac{-3}{2}:\frac{3}{-1}\right).\left(\frac{-9}{2}\right)-\frac{1}{4}< \frac{x}{8}< \frac{-1}{2}.\frac{3}{4}:\frac{1}{8}+1\)
Tìm x,y
a)\(\left(\frac{2}{3}:x+\frac{1}{4}\right)^2=\frac{49}{64}\)
b)\(\frac{2}{5}:\)/x-2/-1/3=1/2
c)\(\frac{1}{8}-\left(\frac{1}{12}-\frac{1}{3}x\right)^3=0\)
Bài 2:
a)\(x+\frac{1}{3}=\frac{3}{4}\)
b)\(\left|x+\frac{1}{8}\right|-\frac{1}{6}=0\)
c)\(\frac{x}{27}=-\frac{2}{36}\)
d)\(\left(x+\frac{1}{2}\right)^2=\frac{1}{16}\)
Tìm x in Za,frac{1}{2}-left(frac{1}{3}+frac{1}{4}right) x frac{1}{48}-left(frac{1}{16}-frac{1}{6}right)b, frac{3}{4}-frac{5}{6}lefrac{x}{12} 1-left(frac{2}{3}-frac{1}{3}right)c, x:left(frac{1}{2}right)^2frac{-1}{2}d,left(x^4right)^2frac{x^{12}}{x^5}left(xne0right)e,frac{3^2.3^8}{27^3}3^xf,2^{x-1}left(16right)^5
Đọc tiếp
Tìm x \(\in\) Z
a,\(\frac{1}{2}-\left(\frac{1}{3}+\frac{1}{4}\right)< x< \frac{1}{48}-\left(\frac{1}{16}-\frac{1}{6}\right)\)
b, \(\frac{3}{4}-\frac{5}{6}\le\frac{x}{12}< 1-\left(\frac{2}{3}-\frac{1}{3}\right)\)
c, \(x:\left(\frac{1}{2}\right)^2=\frac{-1}{2}\)
d,\(\left(x^4\right)^2=\frac{x^{12}}{x^5}\left(x\ne0\right)\)
e,\(\frac{3^2.3^8}{27^3}=3^x\)
f,\(2^{x-1}=\left(16\right)^5\)
\(\frac{x-1}{8}=\frac{2}{x-1}\)
Tìm x:
a) \(\frac{x-1}{2}=\frac{8}{x-1}\)
b) \(\frac{x}{2}=\frac{x}{5}\)
tìm x ,biết:a)frac{2}{left(x+2right)left(x+4right)}+frac{4}{left(x+4right)left(x+8right)}+frac{6}{left(x+8right)left(x+14right)}frac{x}{left(x+2right)left(x+14right)}b)frac{x+1}{10}+frac{x+1}{11}+frac{x+1}{12}frac{x+1}{13}+frac{x+1}{14}c)(x-2)2frac{38}{25}+frac{9}{10}-frac{11}{15}+frac{13}{21}-frac{15}{28}+frac{17}{36}-...+frac{197}{4851}-frac{199}{4950}giúp mk với ,huhu
Đọc tiếp
tìm x ,biết:
a)\(\frac{2}{\left(x+2\right)\left(x+4\right)}+\frac{4}{\left(x+4\right)\left(x+8\right)}+\frac{6}{\left(x+8\right)\left(x+14\right)}=\frac{x}{\left(x+2\right)\left(x+14\right)}\)
b)\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
c)(x-2)2=\(\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-\frac{15}{28}+\frac{17}{36}-...+\frac{197}{4851}-\frac{199}{4950}\)
giúp mk với ,huhu
tìm x ,biết:a)frac{2}{left(x+2right).left(x+4right)}+frac{4}{left(x+4right).left(x+8right)}+frac{6}{left(x+8right).left(x+14right)}frac{x}{left(x+2right).left(x+14right)}b)frac{x+1}{10}+frac{x+1}{11}+frac{x+1}{12}frac{x+1}{13}+frac{x+1}{14}c)left(x-2right)^2frac{38}{25}+frac{9}{10}-frac{11}{15}+frac{13}{21}-frac{15}{28}+frac{17}{36}-..+frac{197}{1851}-frac{199}{1950}giúp mk vs, hu hu
Đọc tiếp
tìm x ,biết:
a)\(\frac{2}{\left(x+2\right).\left(x+4\right)}+\frac{4}{\left(x+4\right).\left(x+8\right)}+\frac{6}{\left(x+8\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
b)\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
c)\(\left(x-2\right)^2=\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-\frac{15}{28}+\frac{17}{36}-..+\frac{197}{1851}-\frac{199}{1950}\)
giúp mk vs, hu hu
tìm x biết:a) left|x+0,573right|2b)left|x+frac{1}{3}right|-4left(-1right)c)1,5.left|3x-1right|+4,6599,103d) left[frac{left(x-4frac{1}{2}right):0,003}{left(3frac{1}{20}-2,65right).4:frac{1}{5}}-frac{left(0,3-frac{3}{20}right).1frac{1}{2}}{left(1,88+2frac{3}{25}right):frac{1}{8}}right]:62frac{1}{20}+17,81:0,0131-13010
Đọc tiếp
tìm x biết:
a) \(\left|x+0,573\right|=2\)
b)\(\left|x+\frac{1}{3}\right|-4=\left(-1\right)\)
c)\(1,5.\left|3x-1\right|+4,659=9,103\)
d) \(\left[\frac{\left(x-4\frac{1}{2}\right):0,003}{\left(3\frac{1}{20}-2,65\right).4:\frac{1}{5}}-\frac{\left(0,3-\frac{3}{20}\right).1\frac{1}{2}}{\left(1,88+2\frac{3}{25}\right):\frac{1}{8}}\right]:62\frac{1}{20}+17,81:0,0131-1301=0\)