Tìm x
A, ( x - 1 )^x+2 = ( x - 1 )^x+4
B, 1/4 × 2/6 × 3/8 × 4/10 × 5/12 ×....× 30/62 × 31/64 = 2^x
tìm x biết
\(\frac{1}{4}.\frac{2}{6}.\frac{3}{8}.\frac{4}{10}.\frac{5}{12}....\frac{30}{62}.\frac{31}{64}=4^x\)
tìm x biết
\(\frac{1}{4}+\frac{2}{6}+\frac{3}{8}+\frac{4}{10}+\frac{5}{12}+...+\frac{30}{62}+\frac{31}{64}=2^x\)
\(\dfrac{1}{4}\cdot\dfrac{2}{6}\cdot\dfrac{3}{8}\cdot\dfrac{4}{10}\cdot\dfrac{5}{12}..........\cdot\dfrac{30}{62}\cdot\dfrac{31}{64}=2\)x
Tìm x, biết:
\(\frac{1}{4}\cdot\frac{2}{6}\cdot\frac{3}{8}\cdot\frac{4}{10}\cdot\frac{5}{12}\cdot.....\cdot\frac{30}{62}\cdot\frac{31}{64}=2^x\)
Tìm x, biết
\(\dfrac{1}{4}\cdot\dfrac{2}{6}\cdot\dfrac{3}{8}\cdot\dfrac{4}{10}\cdot\dfrac{5}{12}\cdot...\cdot\dfrac{30}{62}\cdot\dfrac{31}{64}\)=\(4^x\)
Tìm x biết rằng:
e) \(5^{x+2_{ }^{ }}\) = \(625\);
f) \(\left(x-1\right)^{x+2}\) = \(\left(x+1\right)^{x+4}\);
g) \(\left(2x-1\right)^3=-8\)
h) \(\frac{1}{4}\).\(\frac{2}{6}.\frac{3}{8}.\frac{4}{10}.\frac{5}{12}...\frac{30}{62}.\frac{31}{64}\) = \(2^x\)
Tìm x,biết:
a) -5(x+\(\dfrac{1}{5}\))-\(\dfrac{1}{2}\left(x-\dfrac{2}{3}\right)=\dfrac{3}{2}x-\dfrac{5}{6}\)
b) \(\dfrac{1}{4}\).\(\dfrac{2}{6}\).\(\dfrac{3}{8}\).\(\dfrac{4}{10}\)...\(\dfrac{30}{62}\).\(\dfrac{31}{64}\)=2x
Tìm x,y,z trong dãy tỉ số bằng nhau
1)\(\dfrac{3x}{8}=\dfrac{3y}{64}=\dfrac{3z}{216}\)và \(2x^2+2y^2.z^2=1\)
2) \(\dfrac{2x+1}{5}=\dfrac{4y-5}{9}=\dfrac{2x+4y-4}{7x}\)
3) \(\dfrac{x^3+y^3}{6}=\dfrac{x^3-2y^3}{4}\)và x6 . y6 =14
4) \(\dfrac{x+4}{6}=\dfrac{3y-1}{8}=\dfrac{3y-x-5}{x}\)
5) \(\dfrac{3}{x-1}=\dfrac{4}{y-2}=\dfrac{5}{z-3}\)và x.y.z=192
6)\(\dfrac{x-y}{3}=\dfrac{x+y}{13}=\dfrac{x.y}{200}\)
7)\(\dfrac{x+1}{2}=\dfrac{y-1}{3}=\dfrac{z+2}{4}=\dfrac{x+y+z+2}{2x+5}\)
8) \(\dfrac{15}{x-9}=\dfrac{20}{y-12}=\dfrac{40}{z-24}\)và x.y = 1200
9)\(\dfrac{40}{x-30}=\dfrac{20}{y-15}=\dfrac{28}{z-21}\) và x.y.z = 22400
10)15x = -10y =6z và x.y.z = -30000
11) Cho\(\dfrac{x+1}{3}=\dfrac{y-2}{5}=\dfrac{2z+14}{9}\)và x+z=y
12) Cho \(\dfrac{x}{3}=\dfrac{y}{4}\)và \(\dfrac{y}{5}=\dfrac{z}{6}\).Tính M=\(\dfrac{2x+3y+4z}{3x+4y+5z}\)