\(25\times18\times4\times2=\left(25\times4\right)\times\left(18\times2\right)=100\times36=3600\)

\(\left(-7+3x\right)^4=81\)

\(\Rightarrow\left(-7+3x\right)^4=\left(\pm3\right)^4\)

\(\Rightarrow\left[{}\begin{matrix}-7+3x=3\\-7+3x=-3\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}3x=3--7\\3x=-3--7\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}3x=3+7\\3x=-3+7\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}3x=10\\3x=4\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{10}{3}\\x=\dfrac{4}{3}\end{matrix}\right.\)

Vậy ...

\(\sqrt{9}=3\)

\(\Rightarrow C.3\)

\(\left(-0,12\right)\cdot\left(x-\dfrac{9}{10}\right)=-1,2\)

\(\Rightarrow x-\dfrac{9}{10}=-1,2:\left(-0,12\right)\)

\(\Rightarrow x-\dfrac{9}{10}=10\)

\(\Rightarrow x=10+\dfrac{9}{10}\)

\(\Rightarrow x=\dfrac{109}{10}\)

Vậy...

Ta có:

\(7^3⋮7\) (vì \(7^3=7\cdot7\cdot7\) \(,7⋮7\))

\(26⋮̸\)\(7\)

\(\Rightarrow7^3-26⋮̸\)\(7\) (Vì trong đó có \(26⋮̸7\))

\(C=3+3^2+3^3+3^4+3^5+...+3^{2023}+3^{2024}\)

\(3C=3^2+3^3+3^4+3^5+3^6+...+3^{2024}+3^{2025}\)

\(3C-C=\left(3^2+3^3+3^4+3^5+3^6+...+3^{2024}+3^{2025}\right)-\left(3+3^2+3^3+3^4+3^5+...+3^{2023}+3^{2024}\right)\)\(2C=3^{2025}-3\)

\(C=\dfrac{3^{2025}-3}{2}\)

\(b,\left(-\dfrac{1}{5}\right)^{10}:\left(\dfrac{1}{5}\right)^7\)

Vì \(\left(-\dfrac{1}{5}\right)^{10}=\left(\dfrac{1}{5}\right)^{10}\)nên

\(\Rightarrow\left(\dfrac{1}{5}\right)^{10}:\left(\dfrac{1}{5}\right)^7\)

\(\Rightarrow\left(\dfrac{1}{5}\right)^{10-7}\)

\(\Rightarrow\left(\dfrac{1}{5}\right)^3=\dfrac{1}{125}\)

Công thức:

\(a^m\cdot a^n=a^{m+n}\)

\(a^m:a^n=a^{m-n}\)

\(5\times\left(x+1054\right)=9173\times5\)

\(\Rightarrow5\times\left(x+1054\right)=45865\)

\(\Rightarrow x+1054=45865:5\)

\(\Rightarrow x+1054=9173\)

\(\Rightarrow x=9173-1054\)

\(\Rightarrow x=8119\)

Đề thiếu rồi ạ!

Sửa đề:\(3^{2x-1}+1=28\)

\(3^{2x-1}=28-1\)

\(3^{2x-1}=27\)

\(3^{2x-1}=3^3\)

\(2x-1=3\)

\(2x=3+1\)

\(2x=4\)

\(x=4:2\)

\(x=2\)

Vậy...