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\(23\left(x-1\right)+19=65\)
\(23\left(x-1\right)=65-19\)
\(23\left(x-1\right)=46\)
\(x-1=46:23\)
\(x-1=2\)
\(x=2+1\)
\(x=3\)
\(5x+3x=88\)
\(x\left(5+3\right)=88\)
\(x.8=88\)
\(x=88:8\)
\(x=11\)
\(x^3=64\)
\(x^3=4^3\)
\(\Rightarrow x=4\)
\(\left(5x-4\right):7-2=6\)
\(\left(5x-4\right):7=6+2\)
\(\left(5x-4\right):7=8\)
\(5x-4=8.7\)
\(5x-4=56\)
\(5x=56+4\)
\(5x=60\)
\(x=60:5\)
\(x=12\)
\(x^{50}=x\)
\(\Rightarrow x=1\)
\(4.2^x-3=125\)
\(4.2^x=125+3\)
\(4.2^x=128\)
\(2^x=128:4\)
\(2^x=32\)
\(2^x=2^5\)
\(\Rightarrow x=5\)
k mk nha
1.
a) \(2^x=128\)
\(2^x=2^7\)
\(=>x=7\)
b) \(8^{x-1}=64\)
\(8^{x-1}=8^2\)
\(=>x-1=2\)
\(x=2+1\)
\(=>x=3\)
c) \(3+3^x=30\)
\(3^x=30-3\)
\(3^x=27=3^3\)
\(=>x=3\)
d) \(\left(x+2\right)=64\) -> đề có thiếu không vậy?
e) \(3^2.x=3^5\)
\(x=3^5:3^2\)
\(=>x=3^3=27\)
f) \(\left(2x-1\right)^3=343\)
\(\left(2x-1\right)^3=7^3\)
\(=>2x-1=7\)
\(2x=7+1\)
\(2x=8\)
\(x=8:2\)
\(=>x=4\)
\(#Wendy.Dang\)
a,\(2^x\)=128 b,\(8^{x-1}\)=64 c,3+\(3^x\)=30 d,x+2=64
\(2^7\)=128 \(8^{x-1}\)=\(8^2\) \(3^x\)=30-3 x=64-2
=>x=7 =>x-1=2 \(3^x\)=27 x=62
x=2+1=3 \(3^x\)=\(3^3\)
=>x=3
e,\(3^2\).x=\(3^5\) f,(2x-\(1^3\))=343
x=\(3^5\):\(3^2\) 2x=1+343
x=27 2x=344
x=344:2
x=172
a) |x-3|+|y+4|=1
Xét : \(\hept{\begin{cases}|x-3|\ge0\\|y+4|\ge0\end{cases}}\)
Mà : \(|x-3|+|y+4|=1\)
=) Ix-3I=0 và |y+4|=1 hoặc |y+4|=0 và Ix-3I=1
Nếu : |y+4|=0 và Ix-3I=1
=) |y+4|=0
= ) y + 4 = 0
= ) y = 0 - 4 = -4
=) Ix-3I=1
=) \(\hept{\begin{cases}x-3=-1\\x-3=1\end{cases}}\)=) \(\hept{\begin{cases}x=-1+3=2\\x=1+3=4\end{cases}}\)
Nếu : Ix-3I=0 và |y+4|=1
=) Ix-3I=0
=) x-3=0
=) x = 0 + 3 = 3
=) |y+4|=1
=) \(\hept{\begin{cases}y+4=1\\y+4=-1\end{cases}}\)=)\(\hept{\begin{cases}y=1-4=-3\\y=-1-4=-5\end{cases}}\)
\(\frac{1}{4}+\frac{1}{3}:3x=-5\)
\(\frac{1}{3}:3x=(-5)-\frac{1}{4}\)
\(\frac{1}{3}:3x=\frac{-21}{4}\)
\(\frac{1}{9}\cdot x=\frac{-21}{4}\)
\(x=\frac{-21}{4}:\frac{1}{9}\)
x=\(\frac{-189}{4}\)
Vậy x=\(\frac{-189}{4}\)
\(\frac{1}{4}+\frac{1}{3}:3x=-5\Rightarrow\frac{1}{3}:3x=\left(-5\right)-\frac{1}{4}=\frac{-21}{4}\)
\(3x=\frac{1}{3}:\frac{-21}{4}=\frac{1}{3}.\frac{4}{21}=\frac{4}{63}\)
\(\Rightarrow x=\frac{4}{63}:3=\frac{4}{63}.\frac{1}{3}=\frac{4}{189}\)
ta có \(3x+6=3\left(x+1\right)+3\) chia hết cho x +1 khi 3 chia hết cho x +1
hay ta có \(x+1\in\left\{\pm1,\pm3\right\}\Leftrightarrow x\in\left\{-4,-2,0,2\right\}\)
\(x+2=x-15+17\) chia hết cho x- 15 khi 17 chia hết cho x -15
hay ta có \(x-15\in\left\{\pm1,\pm17\right\}\Leftrightarrow x\in\left\{-2,14,16,32\right\}\)
ta có \(x-7=x-5-2\text{ chia hết cho x-5 khi 2 chia hết cho x-5}\)
hay ta có \(x-5\in\left\{\pm1,\pm2\right\}\Leftrightarrow x\in\left\{3,4,6,7\right\}\)
xuy ra x,y bang
x+3=y.(x+2) Ta co:
x,y=x,y thui wa deeeeeeeeeeeeeee.................
x = -1 và y = -2 ; x = -3 và y = 0 Cách giải chuyển vế qua rooid tách x+3 thàng x+2+1 rồi sẽ có (x+2)(y+1) = -1 rồi phan tích ước của -1 ra và giải theo từng trường hợp
a; \(\dfrac{2}{3}\)\(x\) - \(\dfrac{3}{2}\)\(x\) = \(\dfrac{5}{12}\)
(\(\dfrac{2}{3}\) - \(\dfrac{3}{2}\))\(x\) = \(\dfrac{5}{12}\)
- \(\dfrac{5}{6}\)\(x\) = \(\dfrac{5}{12}\)
\(x\) = \(\dfrac{5}{12}\) : (- \(\dfrac{5}{6}\))
\(x=\) - \(\dfrac{1}{2}\)
Vậy \(x=-\dfrac{1}{2}\)
b; \(\dfrac{2}{5}\) + \(\dfrac{3}{5}\).(3\(x\) - 3,7) = \(\dfrac{-53}{10}\)
\(\dfrac{3}{5}\).(3\(x\) - 3,7) = \(\dfrac{-53}{10}\) - \(\dfrac{2}{5}\)
\(\dfrac{3}{5}\).(3\(x\) - 3,7) = - \(\dfrac{57}{10}\)
3\(x\) - 3,7 = - \(\dfrac{57}{10}\) : \(\dfrac{3}{5}\)
3\(x\) - 3,7 = - \(\dfrac{19}{2}\)
3\(x\) = - \(\dfrac{19}{2}\) + 3,7
3\(x\) = - \(\dfrac{29}{5}\)
\(x\) = - \(\dfrac{29}{5}\) : 3
\(x\) = - \(\dfrac{29}{15}\)
Vậy \(x\) \(\in\) - \(\dfrac{29}{15}\)
(3x-2)³=64
<=>(3x-2)³=4³
=>3x-2=4
<=> x = 2
Vậy x =2
Chúc bạn học tốt
\(\left(3x-2\right)^3=64=4^3\\ \Rightarrow3x-2=4\\ Vậy:\\ 3x=4+2=6\\ Vậy:x=\dfrac{6}{3}=2\)