Cho mình câu chả lời sớm nhất vào 4h30 chiều ngày 28/9/2021

a) (3x +5)³ =121.(-11)

(3x +5)³ = -11³

3x + 5 = -11

3x = -11 - 5

x = \(-\frac{16}{3}\)

b) 3.|2x +1| - 10= |-11|

3.|2x+1| = 11 + 10

|2x+1| = 7

\(\Rightarrow\orbr{\begin{cases}2x+1=7\\2x+1=-7\end{cases}\Rightarrow\orbr{\begin{cases}x=3\\x=-4\end{cases}}}\)

c) 100-(x -5)² = (-6)²

(x-5)² = 8²

x-5 = 8

x = 13

\(\left(3x+5\right)^3=121\left(-11\right)\)

\(\Rightarrow\left(3x+5\right)^3=-1331=\left(-11\right)^3\)

\(\Rightarrow3x+5=-11\)

\(\Rightarrow3x=-16\)

\(\Rightarrow x=-\frac{16}{3}\)

\(3\left|2x+1\right|-10=\left|-11\right|\)

\(\Rightarrow\left|2x+1\right|=7\)

\(\Leftrightarrow\orbr{\begin{cases}2x+1=7\\2x+1=-7\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=3\\x=-4\end{cases}}\)

\(100-\left(x-5\right)^2=\left(-6\right)^2\)

\(\Rightarrow\left(x-5\right)^2=64=\left(\pm8\right)^2\)

\(\Leftrightarrow\orbr{\begin{cases}x-5=8\\x-5=-8\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=13\\x=-3\end{cases}}\)

a) \(10-2\left(4-3x\right)=-4\)

\(2\left(4-3x\right)=10-\left(-4\right)\)

\(2\left(4-3x\right)=14\)

\(4-3x=\dfrac{14}{2}\)

\(4-3x=7\)

\(3x=4-7\)

\(3x=-3\)

\(x=-1\)

b) \(-12+3\left(-x+7\right)=-18\)

\(3\left(-x+7\right)=-18+12\)

\(3\left(-x+7\right)=-6\)

\(-x+7=-2\)

\(-x=-2-7\)

\(-x=-9\)

\(x=9\)

c) \(24:\left(3x-2\right)=-3\)

\(3x-2=24:\left(-3\right)\)

\(3x-2=-8\)

\(3x=-8+2\)

\(3x=-6\)

\(x=-2\)

d) \(-45:5\left(-3-2x\right)=3\)

\(5\left(-3-2x\right)=-45:3\)

\(5\left(-3-2x\right)=-15\)

\(-3-2x=-15:5\)

\(-3-2x=-3\)

\(-2x=-3+3\)

\(-2x=0\)

\(x=0\)

`#3107`

b)

`2.3^x = 162`

`\Rightarrow 3^x = 162 \div 2`

`\Rightarrow 3^x = 81`

`\Rightarrow 3^x = 3^4`

`\Rightarrow x = 4`

Vậy, `x = 4`

c)

`(2x - 15)^5 = (2 - 15)^3`

\(\Rightarrow \)`(2x - 15)^5 - (2x - 15)^3 = 0`

\(\Rightarrow \)`(2x - 15)^3 . [ (2x - 15)^2 - 1] = 0`

\(\Rightarrow\left[{}\begin{matrix}\left(2x-15\right)^3=0\\\left(2x-15\right)^2-1=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x-15=0\\\left(2x-15\right)^2=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x=15\\\left(2x-15\right)^2=\left(\pm1\right)^2\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x-15=1\\2x-15=-1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x=16\\2x=-14\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\x=8\\x=-7\end{matrix}\right.\)

Vậy, `x \in`\(\left\{-7;8;\dfrac{15}{2}\right\}.\)

`d)`

\(3^{x+2}-5.3^x=?\) Bạn ghi tiếp đề nhé!

`e)`

\(7\cdot4^{x-1}+4^{x-1}=23?\)

\(4^{x-1}\cdot\left(7+1\right)=23\\ \Rightarrow4^{x-1}\cdot8=23\\ \Rightarrow4^{x-1}=\dfrac{23}{8}\)

Bạn xem lại đề!

`f)`

\(2\cdot2^{2x}+4^3\cdot4^x=1056\)

\(\Rightarrow2\cdot2^{2x}+\left(2^2\right)^3\cdot\left(2^2\right)^x=1056\\ \Rightarrow2\cdot2^{2x}+2^6\cdot2^{2x}=1056\\ \Rightarrow2^{2x}\cdot\left(2+2^6\right)=1056\\ \Rightarrow2^{2x}\cdot66=1056\\ \Rightarrow2^{2x}=1056\div66\\ \Rightarrow2^{2x}=16\\ \Rightarrow2^{2x}=2^4\\ \Rightarrow2x=4\\ \Rightarrow x=2\)

Vậy, `x = 2`

_____

\(10 -{[(x \div 3+17) \div 10+3.2^4] \div 10}=5\)

\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=10-5\)

\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=5\)

\(\Rightarrow\left(x\div3+17\right)\div10+48=50\)

\(\Rightarrow\left(x\div3+17\right)\div10=2\)

\(\Rightarrow x\div3+17=20\)

\(\Rightarrow x\div3=3\\ \Rightarrow x=9\)

Vậy, `x = 9.`

a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)

\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)

\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)

b) \(\dfrac{39}{7}:x=13\)

\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)

c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)

\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)

\(\dfrac{14}{5}x=34+50=84\)

\(x=\dfrac{84}{\dfrac{14}{5}}=30\)

d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)

\(\dfrac{1}{6}x=\dfrac{5}{12}\)

\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)

g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)

\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)

\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)

\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)

\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)

h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)

\(x=1\)

Mỏi tay woa bn làm nốt nha!!