\(\left(10x-5\right)\cdot25=250\)
^_^^_^^_^
Những câu hỏi liên quan
\(\left(\frac{112}{13.20}+\frac{112}{20.27}+\frac{112}{27.34}+....+\frac{112}{62.69}\right):\left(\frac{5}{9\cdot13}-\frac{7}{9\cdot25}-\frac{9}{19\cdot25}-\frac{31}{19\cdot69}\right)\)
rút gọn biểu thức
a) \(\frac{20^5\cdot5^{10}}{\left(4\cdot25\right)^5}\)b)\(\frac{6^3+3\cdot6^2+3^3}{-13}\)c)\(\frac{125^{12}}{5^{13}\cdot25^{11}}\)d)\(\left(2^{-1}+3^{-1}\right):\left(2^{-1}-3^{-1}\right)+\left(2^{-1}\cdot2^0\right)\cdot2^3\)
e)\(\frac{81^{11}\cdot3^{17}}{27^{10}\cdot9^{15}}\)
Tính A
A=\(\dfrac{3^6\cdot45^4-15^{13}\cdot\left(\dfrac{1}{5}\right)^9}{27^4\cdot25^3+45^6}\)
giúp mk với
\(\left(x-1\right)^2=\left(x-1\right)^4\)
\(5^{-1}\cdot25^x=125\)
Lưu ý: dấu'.' là dấu nhân
Ta có : (x - 1)2 = (x - 1)4
=> (x - 1)4 - (x - 1)2 = 0
=> (x - 1)2.[(x - 1)2 - 1] = 0
=> \(\orbr{\begin{cases}\left(x-1\right)^2=0\\\left(x-1\right)^2-1=0\end{cases}\Rightarrow\orbr{\begin{cases}x-1=0\\\left(x-1\right)^2=1^2\end{cases}\Rightarrow}\orbr{\begin{cases}x-1=0\\x-1=\pm1\end{cases}}}\)
Nếu x - 1 = 0 => x = 1
Nếu x - 1 = 1 => x = 2
Nếu x - 1 = - 1 => x = 0
Vậy \(x\in\left\{0;1;2\right\}\)
b) 5 - 1 . 25x = 125
=> \(\frac{1}{5}.25^x=125\)
=> 25x = 625
=> 25x = 252
=> x = 2
Vậy x = 2
a) \(\left(x-1\right)^2=\left(x-1\right)^4\Leftrightarrow1=\left(x-1\right)^2\)\(\Leftrightarrow x-1=1\Leftrightarrow x=2\)
b) \(5^{-1}.25^x=125\Leftrightarrow5.25^{x-1}=125\Leftrightarrow25^{x-1}=25\)\(\Rightarrow x-1=1\Leftrightarrow x=2\)
Tính A
A=\(\dfrac{3^6\cdot45^4-15^{13}\cdot\left(\dfrac{1}{5}\right)^9}{27^4\cdot25^3+45^6}\)
\(A=\dfrac{3^6.45^4-15^{13}.\left(\dfrac{1}{5}\right)^9}{27^4.25^3+45^6}\)
\(=\dfrac{3^6.3^8.5^4-5^{13}.3^{13}.\left(\dfrac{1}{5}\right)^9}{3^{12}.5^6+3^{12}.5^6}\)
\(=\dfrac{3^{14}.5^4-5^{13}.3^{13}.\left(\dfrac{1}{5}\right)^9}{3^{12}.5^6+3^{12}.5^6}\)
\(=\dfrac{3^{13}\left[3.5^4-5^{13}.\left(\dfrac{1}{5}\right)^9\right]}{3^{12}(5^6+5^6)}\)
\(=\dfrac{3^{13}.1250}{3^{12}.31250}\)
\(=\dfrac{3^{13}.5^4.2}{3^{12}.5^6.2}\)
\(=\dfrac{3}{5^2}=\dfrac{3}{25}\)
Vậy \(A=\dfrac{3}{25}\)
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Rút gọn biểu thức: \(\left(2x-5\right)\left(4x^2+10x+25\right)\left(2x+5\right)\left(4x^2-10x+25\right)-^4\)\(64x^4\)
Chỗ cuối mình viết nhầm nha là \(64x^4\)
Võ Thị Thảo Minh
em hãy sử dụng đẳng thức này để rút gọn :
a2 - b2 = (a - b)(a + b)
và đẳng thức này nx quên mất :)) k hack điểm gì cả nhé
(a + b + c)3 = a3 + b3 + c3 + 3(a + b)(b + c)(a + c)
Xem thêm câu trả lời
Tính A
A=\dfrac{3^6\cdot45^4-15^{13}\cdot\left(\dfrac{1}{5}\right)^9}{27^4\cdot25^3+45^6}
Tính A
A=\dfrac{3^6\cdot45^4-15^{13}\cdot\left(\dfrac{1}{5}\right)^9}{27^4\cdot25^3+45^6}
Tính
A=\(\dfrac{3^6\cdot45^4-15^{13}\cdot\left(\dfrac{1}{5}\right)^9}{27^4\cdot25^3+45^6}\)
