a) \(2^{3x+2}=4^{x+5}\Leftrightarrow2^{3x+2}=2^{2\left(x+5\right)}\Leftrightarrow2^{3x+2}=2^{2x+10}\)
\(\Rightarrow3x+2=2x+10\Leftrightarrow3x+2-2x-10\)
\(\Leftrightarrow x-8=0\Leftrightarrow x=8\) vậy \(x=8\)
1)A=\(\dfrac{5}{1\cdot2}+\dfrac{5}{2\cdot3}+.....+\dfrac{5}{99\cdot100}\)
C=\(1\cdot2\cdot3+2\cdot3\cdot4++3\cdot4\cdot5+4\cdot5\cdot6+5\cdot6\cdot7+6\cdot7\cdot8+7\cdot8\cdot9+8\cdot9\cdot10\)
D=\(1^2+2^2+3^2+...+99^2+100^2\)
Tìm số x , biết
a) \(\dfrac{2}{3}x-\dfrac{3}{2}x=\dfrac{5}{12}\)
b) \(\dfrac{2}{5}+\dfrac{3}{5}.\left(3x-3,7\right)=-\dfrac{53}{10}\)
c) \(\dfrac{7}{9}:\left(2+\dfrac{3}{4}x\right)+\dfrac{5}{9}=\dfrac{23}{27}\)
d) \(\dfrac{-2}{3}.x+\dfrac{1}{5}=\dfrac{3}{10}\)
e) \(\left|x\right|-\dfrac{3}{4}=\dfrac{5}{3}\)
f) \(\left|2x-\dfrac{1}{3}\right|+\dfrac{5}{6}=1\)
\(B=5\dfrac{9}{10}:\dfrac{3}{2}-\left(2\dfrac{1}{3}\cdot4\dfrac{1}{2}-2\cdot2\dfrac{1}{3}\right):\dfrac{7}{4}\)
a, \(\dfrac{5}{2}-3\left(\dfrac{1}{3}-x\right)=\dfrac{1}{4}-7x\)
b,\(60\%.x+\dfrac{2}{3}.x=\dfrac{1}{3}.6\dfrac{1}{3}\)
c, \(\left(\dfrac{9}{2}.x-2x\right).\left(-1\dfrac{4}{7}\right)=\dfrac{11}{4}\)
d,\(\left(x+\dfrac{5}{6}\right).2\dfrac{2}{5}-1\dfrac{1}{4}=35\%\)
Tìm x biết:
\(\dfrac{4}{7}+\dfrac{3}{7}:x=-5\)
b)\(\dfrac{-1}{2}x+\dfrac{2}{3}.\dfrac{-5}{4}=\dfrac{3}{5}-\dfrac{5}{6}\)
Đề bài: Tìm x, biết:
a) 390 - ( x - 7) = 13 mũ 2 : 12
b) ( x - 35 . 2 mũ 2) : 7= 3 mũ 3 - 24
c) x - 6 : 2 - ( 4 mũ 2 . 3 - 24) : 2 : 6 = 3
d) 4 . x - 5 = 5 + 5 mũ 2 +5 mũ 3 + ..... + 5 mũ 99
e) ( 2 . x - 1 ) mũ 4 = 625
a\(\dfrac{5}{6}x-\dfrac{2}{3}=3\dfrac{1}{2}\)
b\(\dfrac{4}{5}-\dfrac{3}{4}\div x=0,3\)
c\(\dfrac{-3}{2}-\dfrac{1}{4}x=1\dfrac{1}{3}-0,2x\)
d\(\left|\dfrac{3}{5}x+\dfrac{4}{3}\right|:\dfrac{2}{3}-0,5=1\dfrac{1}{2}\)
e\(\dfrac{4x-5}{2-3x}=\dfrac{3}{4}\)
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thực hiện phép tính
a, (-3/4+ 5/6): (2/9 - 7/12)
Tìm x, biết:
a, 1,5+ 1/1/4 x= 2/3
b, (2,7 x - 1/1/2 x) : 2/7= -21/4
c, 5/8 +1/3: x = 1/2
d, -5/6+ 8/3 + -29/6 < x < -1/2+ 2+ 5/2 ( với x thuộc Z)
tìm x
a\(\dfrac{6}{7}x+\dfrac{5}{6}x=\dfrac{3}{4}\)
b\(\dfrac{5}{4}-\dfrac{3}{5}\div x=1\dfrac{1}{3}\)
c\(\left(\dfrac{4}{7}x-\dfrac{1}{3}\right)\div3\dfrac{1}{2}=0,5\)
d\(\dfrac{4}{5}-\dfrac{2}{3}x=1\dfrac{1}{4}+2,5x\)
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