\(\Leftrightarrow2^{4x+2}=2^{-6}\)
=>4x+2=-6
=>4x=-8
hay x=-2
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a,dfrac{8^{20}+4^{20}}{4^{25}+64^5}b,left(1+dfrac{2}{3}-dfrac{1}{4}right).left(dfrac{4}{5}-dfrac{3}{4}right)^2c,23dfrac{1}{3}:left(dfrac{-5}{7}right)-13dfrac{1}{3}:left(dfrac{-5}{7}right)d,1:left(dfrac{2}{3}-dfrac{3}{4}right)^2e,dfrac{45^{10}.5^{20}}{75^{15}}
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a,\(\dfrac{8^{20}+4^{20}}{4^{25}+64^5}\)
b,\(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)
c,\(23\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)-13\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)\)
d,1:\(\left(\dfrac{2}{3}-\dfrac{3}{4}\right)^2\)
e,\(\dfrac{45^{10}.5^{20}}{75^{15}}\)
Tìm x.
\(1,\dfrac{3}{2}\left(x-\dfrac{1}{3}\right)-\dfrac{1}{2}\left(x+\dfrac{1}{2}\right)=\dfrac{1}{4}\)
\(2,3\left(x-2\right)-4\left(x+2\right)=x+2\)
\(3,4x\left(x-1\right)+4x-2\left(x+1\right)=-2\)
\(4,x\left(x+2\right)-3\left(x-1\right)=3\left(x+1\right)\)
Tính
a) \(2\sqrt{\dfrac{25}{16}}-3\sqrt{\dfrac{49}{36}}+4\sqrt{\dfrac{81}{64}}\)
b) \(\left(3\sqrt{2}\right)^2-\left(4\sqrt{\dfrac{1}{2}}\right)^2+\dfrac{1}{16}.\left(\sqrt{\dfrac{3}{4}}\right)^2\)
c) \(\dfrac{2}{3}\sqrt{\dfrac{81}{16}}-\dfrac{3}{4}\sqrt{\dfrac{64}{9}}+\dfrac{7}{5}.\sqrt{\dfrac{25}{196}}\)
Tìm x, y, zϵ R biết: \(\left(4x^2-4x+1\right)^{2022}+\left(y^2-\dfrac{4}{5}y+\dfrac{4}{25}\right)^{2022}+\left|x+y-z\right|=0\)
1. Giải a,sqrt{4}-sqrt{9x}+sqrt{25x}8 b,sqrt{dfrac{1}{4x}}+sqrt{dfrac{1}{9x}}-sqrt{dfrac{1}{36x}}dfrac{2}{3}
2. Adfrac{1}{sqrt{1cdot2018}}+dfrac{1}{sqrt{2cdot2017}}+...+dfrac{1}{sqrt{kleft(2018-k+1right)}}+...+dfrac{1}{sqrt{2018cdot1}}
So sánh A với 2cdotdfrac{2018}{2019}
3.Cho abc201. Tínhdfrac{201a}{ab+201+a+201}+dfrac{b}{cb+b+201}+dfrac{c}{ac+c+1}
4.Bleft(dfrac{1-x^3}{1-x}+xright)cdotleft(dfrac{1+x^3}{1+x}-xright) a, Rút gọn B b, tìm x đ...
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1. Giải \(a,\sqrt{4}-\sqrt{9x}+\sqrt{25x}=8\) \(b,\sqrt{\dfrac{1}{4x}}+\sqrt{\dfrac{1}{9x}}-\sqrt{\dfrac{1}{36x}}=\dfrac{2}{3}\)
2. \(A=\dfrac{1}{\sqrt{1\cdot2018}}+\dfrac{1}{\sqrt{2\cdot2017}}+...+\dfrac{1}{\sqrt{k\left(2018-k+1\right)}}+...+\dfrac{1}{\sqrt{2018\cdot1}}\)
So sánh A với \(2\cdot\dfrac{2018}{2019}\)
3.Cho abc=201. Tính\(\dfrac{201a}{ab+201+a+201}+\dfrac{b}{cb+b+201}+\dfrac{c}{ac+c+1}\)
4.\(B=\left(\dfrac{1-x^3}{1-x}+x\right)\cdot\left(\dfrac{1+x^3}{1+x}-x\right)\) a, Rút gọn B b, tìm x để B=64
5. Tìm x: \(\left|x-2\right|-2\left|x+1\right|=3-2\left(1-2x\right)\)
a) \(\left[\dfrac{3}{2}x+\dfrac{1}{2}\right]=\left(4x-1\right)\)
Tìm x:
a, \(\left(x+2\right)^2=\dfrac{1}{2}-\dfrac{1}{3}\)
b, \(\left(x-1\right)^{x+2}=\left(x-1\right)^2\)
c, \(\left(1-3x\right)^3=-64\)
1. Tính giá trị biểu thức sau bằng cách hợp lí
\(\dfrac{1-\dfrac{1}{\sqrt{49}}+\dfrac{1}{49}-\dfrac{1}{\left(7\sqrt{7}\right)^2}}{\dfrac{\sqrt{64}}{2}-\dfrac{4}{7}+\left(\dfrac{2}{7}\right)^2-\dfrac{4}{343}}\)
Tìm x,y biết:
a) \(3\dfrac{1}{2}-\dfrac{2}{3}:\left(1-2x\right)=1\dfrac{1}{2}\)
b) \(\dfrac{-1.5}{3\left|2x+1\right|}=\dfrac{\sqrt{64}}{-112}\)