a: \(=12\cdot\dfrac{4}{9}+\dfrac{4}{3}=\dfrac{4}{3}\cdot4+\dfrac{4}{3}=\dfrac{4}{3}\cdot5=\dfrac{20}{3}\)
b: \(=\dfrac{-5}{7}\cdot\left(12.5+1.5\right)=\dfrac{-5}{7}\cdot14=-10\)
1)Tìm x, biết :
\(4.\left[3x-1\right]+\left[x\right]-2.\left[x-5\right]+7.\left[x-3\right]=12\)
\(\left[2\dfrac{1}{5}-x\right]+\left[x-\dfrac{1}{5}\right]+8\dfrac{1}{5}=1,2\)
\(3.\left[x+4\right]-\left[2.x+1\right]-5.\left[x-3\right]+\left[x-9\right]=5\)
\(2\left[x+3\dfrac{1}{2}\right]+\left[x\right]-3\dfrac{1}{2}=\left[2\dfrac{1}{5}-x\right]\)
Câu 1:Thực hiện phép tính(tính một cách hợp lí nếu có thể):
a)\(\dfrac{1}{2}-\dfrac{-3}{6}=+\dfrac{5}{3}-\dfrac{9}{12}\)
b)\(\begin{matrix}&\left(\dfrac{-2}{3}\right)\end{matrix}.\dfrac{3}{11}+\left(\dfrac{-16}{9}\right):\dfrac{11}{3}\)
c)\(\begin{matrix}&\left(\dfrac{2}{3}\right)^0\end{matrix}-\sqrt{9+}\left(-\dfrac{^{ }1}{2}\right)^2\)
Thực hiện phép tính biết:
a) \(\dfrac{2}{3}:\dfrac{-5}{3}+\dfrac{7}{5}\)
b) \(3^7:3^5+\left|-2\right|.5^2\)
Tìm x biết:
a) \(\left(-\dfrac{2}{3}\right)^2.x=\left(-\dfrac{2}{3}\right)^5\) ; b) \(\left(-\dfrac{1}{3}\right)^3.x=\dfrac{1}{81}\) ; c) (2x-3)\(^2\) ; d) (3x-2)\(^5\) =-243
Cho : P= \(\dfrac{7!.3!}{10!}.\left(\dfrac{8!}{3!.5!}-\dfrac{9!}{2!.5!}\right)+10\) .Tính phần nguyên của P
\(\left(\dfrac{3}{5}\right)^6.\left(\dfrac{5}{3}\right)^3\)
so sánh: \(\left(\dfrac{16}{25}\right)^{10}\) và\(\left(\dfrac{3}{7}\right)^{40}\)
a, \(\dfrac{\left(-3\right)^x}{81}=-27\)
b, \(2^{x-1}=16\)
c, \(\left(x-1\right)^2=25\)
d, \(0,2-\left|4,2-2x\right|=0\)
e, \(1\dfrac{2}{3}:\dfrac{x}{4}=6:0,3\)
\(\left(\dfrac{32}{243}\right)^x=\left(\dfrac{3}{2}\right)^{-1}\)
