a)( \(\dfrac{-3}{4}\))\(^{^{ }3x-1}\)=\(\dfrac{256}{81}\)
b) (x-7)\(^{x+1}\) - (x-7)\(^{x+11}\) = 0
c)(x - \(\dfrac{1}{2}\))\(^2\) + (y + \(\dfrac{1}{2}\))\(^2\) =0
Những câu hỏi liên quan
1) left(dfrac{-3}{4}right)^{3x+1}dfrac{81}{256} 6) left(8x-1right)^{2n-4}5^{2n-4}
2) 172.x^2-dfrac{7^9}{98^3}dfrac{1}{2^3} 7) left(dfrac{1}{2x}-5right)^{20}+left(y^2-dfrac{1}{4}right)^{10}0
3) left(x-dfrac{2}{9}right)^3left(dfrac{2}{3}right)^6
4) left(x+2right)^2+left(y-dfrac{1}{10}right)^20
5) left(x-7right)^{n+1}-left(x-7right)^{n+11}0
Giúp mk với!!...
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1) \(\left(\dfrac{-3}{4}\right)^{3x+1}=\dfrac{81}{256}\) 6) \(\left(8x-1\right)^{2n-4}=5^{2n-4}\)
2) \(172.x^2-\dfrac{7^9}{98^3}=\dfrac{1}{2^3}\) 7) \(\left(\dfrac{1}{2x}-5\right)^{20}+\left(y^2-\dfrac{1}{4}\right)^{10}=0\)
3) \(\left(x-\dfrac{2}{9}\right)^3=\left(\dfrac{2}{3}\right)^6\)
4) \(\left(x+2\right)^2+\left(y-\dfrac{1}{10}\right)^2=0\)
5) \(\left(x-7\right)^{n+1}-\left(x-7\right)^{n+11}=0\)
Giúp mk với!!!!!
1: =>3x+1=4
=>3x=3
hay x=1
2: \(\Leftrightarrow172\cdot x^2=\dfrac{1}{2^3}+\dfrac{7^9}{98^3}=\dfrac{1}{2^3}+\dfrac{7^9}{7^6\cdot2^3}\)
\(\Leftrightarrow172\cdot x^2=\dfrac{1}{2^3}+\dfrac{7^3}{2^3}=\dfrac{344}{2^3}\)
\(\Leftrightarrow x^2=\dfrac{1}{4}\)
=>x=1/2 hoặc x=-1/2
3: \(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{2}{9}=\dfrac{4}{9}\\x-\dfrac{2}{9}=-\dfrac{4}{9}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{3}\\x=-\dfrac{2}{9}\end{matrix}\right.\)
4: =>x+2=0 và y-1/10=0
=>x=-2 và y=1/10
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tìm x:
\(a,5^x.\left(5^2\right)^3=625\)
\(b,\left(\dfrac{12}{15}\right)^x=\left(\dfrac{5}{4}\right)^{-2}-\left(\dfrac{-3}{5}\right)^4\)
\(c,\left(\dfrac{-3}{4}\right)^{3x-1}=\dfrac{256}{81}\)
\(d,172x^2-7^9:98^3=2^{-3}\)
tìm x biết:
a) \(5^x.\left(5^3\right)^2=625\)
b)\(\left(\dfrac{12}{15}\right)^x=\left(\dfrac{5}{3}\right)^{-5}-\left(-\dfrac{3}{5}\right)^4\)
c)\(\left(-\dfrac{3}{4}\right)^{3x-1}=\dfrac{256}{81}\)
d)\(172x^2-7^9:98^3=2^{-3}\)
Tìm x biết:
a) dfrac{-32}{left(-2right)^x}4 f) left(3x-1right)^3dfrac{-8}{27}
b) left(dfrac{1}{2}right)^{2x-1}dfrac{1}{8} g) left(2x+3right)^2dfrac{9}{121}
c) dfrac{1}{9}.27^x3^x h) 5^x+5^{x+2}650
d) 9^x:3^3dfrac{1}{243} i) left(x-7right)^{x+1}-left(x-7right)0
e) dfrac{x7}{81}27...
Đọc tiếp
Tìm x biết:
a) \(\dfrac{-32}{\left(-2\right)^x}=4\) f) \(\left(3x-1\right)^3=\dfrac{-8}{27}\)
b) \(\left(\dfrac{1}{2}\right)^{2x-1}=\dfrac{1}{8}\) g) \(\left(2x+3\right)^2=\dfrac{9}{121}\)
c) \(\dfrac{1}{9}.27^x=3^x\) h) \(5^x+5^{x+2}=650\)
d) \(9^x:3^3=\dfrac{1}{243}\) i) \(\left(x-7\right)^{x+1}-\left(x-7\right)=0\)
e) \(\dfrac{x7}{81}=27\) m) \(\left(\dfrac{-3}{4}\right)^{3x-1}=\dfrac{256}{81}\)
h) \(5^x+5^{x+2}=650\)
\(\Leftrightarrow5^x+5^x.5^2=650\)
\(\Leftrightarrow5^x\left(1+25\right)=650\)
\(\Leftrightarrow5^x.26=650\)
\(\Leftrightarrow5^x=25\)
\(\Leftrightarrow x=2\)
haizzz,đăng ít thôi,chứ nhìn hoa mắt quá =.=
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giả phương trình
dfrac{x+1}{2}+dfrac{3x-2}{3}dfrac{x-7}{12}
b) dfrac{2x}{x-3}-dfrac{5}{x+3}dfrac{x^2+21}{x^2-9}
c) x3+2x 0
d) ( x-4) (7x-3) -x2+160
e) 2x-42
g) (x+2)(x-3) 0
h) dfrac{2}{x+1}-dfrac{1}{x-2}dfrac{3x-11}{left(x+1right).left(x-2right)}
dfrac{ }{ }
i) dfrac{1}{x+2}+dfrac{5}{x-2}dfrac{2x-12}{x^2-4}
Đọc tiếp
giả phương trình
\(\dfrac{x+1}{2}+\dfrac{3x-2}{3}=\dfrac{x-7}{12}\)
b) \(\dfrac{2x}{x-3}-\dfrac{5}{x+3}=\dfrac{x^2+21}{x^2-9}\)
c) x3+2x = 0
d) ( x-4) (7x-3) -x2+16=0
e) 2x-4=2
g) (x+2)(x-3) = 0
h) \(\dfrac{2}{x+1}-\dfrac{1}{x-2}=\dfrac{3x-11}{\left(x+1\right).\left(x-2\right)}
\dfrac{ }{ }\)
i) \(\dfrac{1}{x+2}+\dfrac{5}{x-2}=\dfrac{2x-12}{x^2-4}\)
a) \(\dfrac{x+1}{2}+\dfrac{3x-2}{3}=\dfrac{x-7}{12}\)
\(\Leftrightarrow\dfrac{6\left(x+1\right)+4\left(3x-2\right)}{12}=\dfrac{x-7}{12}\)
\(\Leftrightarrow6\left(x+1\right)+4\left(3x-2\right)=x-7\)
\(\Leftrightarrow6x+6+12x-8=x-7\)
\(\Leftrightarrow6x+12x-x=-7-6+8\)
\(\Leftrightarrow17x=-5\)
\(\Leftrightarrow x=\dfrac{-5}{17}\)
Vậy .........................
b) \(\dfrac{2x}{x-3}-\dfrac{5}{x+3}=\dfrac{x^2+21}{x^2-9}\left(ĐKXĐ:x\ne\pm3\right)\)
\(\Leftrightarrow\dfrac{2x\left(x+3\right)-5\left(x-3\right)}{\left(x-3\right)\left(x+3\right)}=\dfrac{x^2+21}{\left(x-3\right)\left(x+3\right)}\)
\(\Rightarrow2x\left(x+3\right)-5\left(x-3\right)=x^2+21\)
\(\Leftrightarrow2x^2+6x-5x+15=x^2+21\)
\(\Leftrightarrow2x^2-x^2+x+15-21=0\)
\(\Leftrightarrow x^2+x-6=0\)
\(\Leftrightarrow x^2-2x+3x-6=0\)
\(\Leftrightarrow x\left(x-2\right)+3\left(x-2\right)=0\)
\(\Leftrightarrow\left(x-2\right)\left(x+3\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-2=0\\x+3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2\left(n\right)\\x=-3\left(l\right)\end{matrix}\right.\)
Vậy \(S=\left\{2\right\}\)
d) \(\left(x-4\right)\left(7x-3\right)-x^2+16=0\)
\(\Leftrightarrow\left(x-4\right)\left(7x-3\right)-\left(x^2-16\right)=0\)
\(\Leftrightarrow\left(x-4\right)\left(7x-3\right)-\left(x-4\right)\left(x+4\right)=0\)
\(\Leftrightarrow\left(x-4\right)\left(7x-3-x-4\right)=0\)
\(\Leftrightarrow\left(x-4\right)\left(6x-7\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\6x-7=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=\dfrac{7}{6}\end{matrix}\right.\)
Vậy .........................
P/s: các câu còn lại tương tự, bn tự giải nha
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8 tháng 2 2022 lúc 20:37
a) \(\dfrac{5x-2}{3}+x=1+\dfrac{5-3x}{2}\)
b) \(\dfrac{\left(3x-1\right)\left(x+2\right)}{3}-\dfrac{2x^2+1}{2}=\dfrac{11}{2}\)
c) \(x-\dfrac{5x+2}{6}=\dfrac{7-3x}{4}\)
d) \(\dfrac{x-1}{2}+\dfrac{x-1}{3}-\dfrac{x-1}{6}=2\)
a, \(\Rightarrow10x-4+6x=6+15-9x\Leftrightarrow7x=25\Leftrightarrow x=\dfrac{25}{7}\)
b, \(\Rightarrow2\left(3x^2+5x-2\right)-6x^2-3=33\Leftrightarrow10x-7=33\Leftrightarrow x=4\)
c, \(\Rightarrow12x-10x-4=21-9x\Leftrightarrow11x=25\Leftrightarrow x=\dfrac{25}{11}\)
d, \(\Rightarrow3x-3+2x-2-x+1=12\Leftrightarrow4x=16\Leftrightarrow x=4\)
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\(\dfrac{5x-2}{3}+x=1+\dfrac{5-3x}{2}\)
\(\Leftrightarrow\dfrac{5x-2+3x}{3}=\dfrac{2+5-3x}{2}\)
\(\Leftrightarrow\dfrac{8x-2}{3}=\dfrac{7-3x}{2}\)
\(\Leftrightarrow16x-4=21-9x\)
\(\Leftrightarrow16x+9x=21+4\)
\(\Leftrightarrow25x=25\)
\(\Leftrightarrow x=1\)
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\(a,\dfrac{5x-2}{3}+x=1+\dfrac{-3x+5}{2}\)
\(2\left(5x-2\right)+6x=-9x+21\)
\(16x+9x=21+4\)
\(25x=25\)
\(x=1\)
\(b,\dfrac{3x^2+5x-2}{3}-\dfrac{2x^2+1}{2}=\dfrac{11}{2}\)
\(\dfrac{6x^2=10x-4-6x^2-3}{6}=\dfrac{11}{2}\)
\(\dfrac{10x-4-3}{6}=\dfrac{11}{2}\)
\(\dfrac{10x-7}{6}=\dfrac{11}{2}\)
\(10x=33+7\)
\(x=4\)
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tìm x :
a) dfrac{x+1}{7}+dfrac{x+1}{8}dfrac{x+1}{9}+dfrac{x+1}{10}
b) dfrac{x+1}{12}+dfrac{x^2}{11}dfrac{x+3}{10}+dfrac{x+4}{9}
c) dfrac{x-2}{x-1}dfrac{x+4}{x+7}
d)dfrac{3x+2}{5x+7}dfrac{3x-1}{5x-3}
2 tìm x,y,z
a) dfrac{x}{2}dfrac{y}{3},dfrac{y}{4}dfrac{z}{5}vàx^2-y^2-16
b)2x3y,5x7z và 3x-7y+5z30
Đọc tiếp
tìm x :
a) \(\dfrac{x+1}{7}+\dfrac{x+1}{8}=\dfrac{x+1}{9}+\dfrac{x+1}{10}\)
b) \(\dfrac{x+1}{12}+\dfrac{x^2}{11}=\dfrac{x+3}{10}+\dfrac{x+4}{9}\)
c) \(\dfrac{x-2}{x-1}=\dfrac{x+4}{x+7}\)
d)\(\dfrac{3x+2}{5x+7}=\dfrac{3x-1}{5x-3}\)
2 tìm x,y,z
a) \(\dfrac{x}{2}=\dfrac{y}{3},\dfrac{y}{4}=\dfrac{z}{5}vàx^2-y^2=-16\)
b)2x=3y,5x=7z và 3x-7y+5z=30
a.dfrac{4x-5}{x-1}2+dfrac{x}{x-1} b.dfrac{7}{x+2}dfrac{3}{x-5} c.dfrac{2x+5}{2x}-dfrac{x}{x+5}0d.dfrac{12x+1}{11x-4}+dfrac{10x-4}{9}dfrac{20x+17}{18} e.dfrac{11}{x}dfrac{9}{x+1}+dfrac{2}{x-4} f.dfrac{14}{3x-12}-dfrac{2+x}{x-4}dfrac{3}{8-2x}-dfrac{5}{6}m.dfrac{12}{1-9x^2}dfrac{1+3x}{1+3x}-dfrac{1+3x}{1-3x} n.dfrac{x+1}{x-1}-dfrac{x-1}{x+1}dfrac{16}{x^2} e.left(1-dfrac{x-1}{x+1}right)left(x+2right)dfrac{x+1}{x-1}+dfrac{x-1}{x+1}
Đọc tiếp
a.\(\dfrac{4x-5}{x-1}=2+\dfrac{x}{x-1}\) b.\(\dfrac{7}{x+2}=\dfrac{3}{x-5}\) c.\(\dfrac{2x+5}{2x}-\dfrac{x}{x+5}=0\)
d.\(\dfrac{12x+1}{11x-4}+\dfrac{10x-4}{9}=\dfrac{20x+17}{18}\) e.\(\dfrac{11}{x}=\dfrac{9}{x+1}+\dfrac{2}{x-4}\) f.\(\dfrac{14}{3x-12}-\dfrac{2+x}{x-4}=\dfrac{3}{8-2x}-\dfrac{5}{6}\)
m.\(\dfrac{12}{1-9x^2}=\dfrac{1+3x}{1+3x}-\dfrac{1+3x}{1-3x}\) n.\(\dfrac{x+1}{x-1}-\dfrac{x-1}{x+1}=\dfrac{16}{x^2}\) e.\(\left(1-\dfrac{x-1}{x+1}\right)\left(x+2\right)=\dfrac{x+1}{x-1}+\dfrac{x-1}{x+1}\)
bạn tách một câu vài câu hỏi chứ đừng gộp như thế này ko ai trả lời đâu
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a: =>\(4x-5=2x-2+x=3x-2\)
=>x=3
b: \(\Leftrightarrow7x-35=3x+6\)
=>4x=41
=>x=41/4
c: =>(2x+5)(x+5)-2x^2=0
=>2x^2+10x+5x+25-2x^2=0
=>15x=-25
=>x=-5/3
e: \(\Leftrightarrow\dfrac{11}{x}=\dfrac{9x-36+2x+2}{\left(x+1\right)\left(x-4\right)}\)
=>11(x^2-3x-4)=x(11x-34)
=>11x^2-33x-44=11x^2-34x
=>x=44
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tính giới hạn của các hàm số sau:a, limx→0dfrac{sqrt{1+x}-sqrt{1-x}}{sqrt[3]{1+x}-sqrt{1-x}}b, limx→0(dfrac{1}{x}-dfrac{1}{x^2})c, limx→+∞ dfrac{x^4-x^3+11}{2x-7}d, limx→5 ( dfrac{7}{left(x-1right)^2}.dfrac{2x+1}{2x-3} )
Đọc tiếp
tính giới hạn của các hàm số sau:
a, limx→0\(\dfrac{\sqrt{1+x}-\sqrt{1-x}}{\sqrt[3]{1+x}-\sqrt{1-x}}\)
b, limx→0(\(\dfrac{1}{x}-\dfrac{1}{x^2}\))
c, limx→+∞ \(\dfrac{x^4-x^3+11}{2x-7}\)
d, limx→5 ( \(\dfrac{7}{\left(x-1\right)^2}.\dfrac{2x+1}{2x-3}\) )
a. Áp dụng công thức L'Hospital:
\(\lim\limits_{x\to 0}\frac{\sqrt{x+1}-\sqrt{1-x}}{\sqrt[3]{x+1}-\sqrt{1-x}}=\lim\limits_{x\to 0}\frac{\frac{1}{2}(x+1)^{\frac{-1}{2}}+\frac{1}{2}(1-x)^{\frac{-1}{2}}}{\frac{1}{3}(x+1)^{\frac{-2}{3}}+\frac{1}{2}(1-x)^{\frac{-1}{2}}}=\frac{1}{\frac{5}{6}}=\frac{6}{5}\)
b.
\(\lim\limits_{x\to 0}(\frac{1}{x}-\frac{1}{x^2})=\lim\limits_{x\to 0}\frac{x-1}{x^2}=-\infty\)
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c. Áp dụng quy tắc L'Hospital:
\(\lim\limits_{x\to +\infty}\frac{x^4-x^3+11}{2x-7}=\lim\limits_{x\to +\infty}\frac{4x^3-3x^2}{2}=+\infty \)
d.
\(\lim\limits_{x\to 5}\frac{7}{(x-1)^2}.\frac{2x+1}{2x-3}=\frac{7}{(5-1)^2}.\frac{2.5+11}{2.5-3}=\frac{11}{16}\)
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