Tìm x,y: (5x+1)^2=36/49=(2y-1)^3
(x-2/9)^3=(2/3)^6=(y/3)^2
(8x-1)^2y+1=5^2y+1 (với y thuộc N)
1. Tìm x, biết :
a) 27x : 3x = 9
b) 25 : 5x = 5
c) 2 : (x + 2)2 = \(\dfrac{1}{18}\)
d) (5x - 1)2 = \(\dfrac{36}{49}\)
e) \(\left(\dfrac{3}{4}\right)^x=\dfrac{2^8}{3^4}\)
g) \(\left(\dfrac{-2}{5}\right)^x=\dfrac{16}{625}\)
h) 5(x-2)(x+3)=(-17)0
i) (x - 2)8=(x - 2)6
k) (x + 1)7=(x + 1)5
l) (3x - 1)2n+1=82n+1
1.Tính:
\(\left(\dfrac{-2}{3}\right)\)\(\times0.75+1\dfrac{2}{3}\div\left(\dfrac{-4}{9}\right)+\left(\dfrac{-1}{2}\right)^2\)
2.Tìm x:
a)\(\dfrac{3}{4}-\left(x+\dfrac{1}{2}\right)=\dfrac{4}{5}\)
b) \(\left|x-\dfrac{2}{5}\right|+\dfrac{3}{4}=\dfrac{11}{4}\)
3.Tìm n, biết:
a) \(\dfrac{16}{2^n}=2\)
b)\(\dfrac{\left(-3\right)^n}{81}=-27\)
4. Tìm ba số x,y,z biết:
\(\dfrac{x}{2}=\dfrac{y}{3};\dfrac{y}{5}=\dfrac{z}{4}\)và x-y+z= -49
a, 4*(3-x)^10=9(3-x)^8
b, (x-1)^x+3=(x-1)^x+1
Tìm x :
a)\(\dfrac{x-1}{50}+\dfrac{x-2}{49}=\dfrac{x-3}{48}+\dfrac{x-4}{47}\)
b)\(\dfrac{x+25}{6}+\dfrac{x+20}{11}+\dfrac{x+16}{15}+3=0\)
c)\(\dfrac{x-15}{6}+\dfrac{x-10}{11}=\dfrac{x-3}{18}+\dfrac{x-7}{14}\)
Tìm x,biết
1) 1 7/9:2 2/3=2 2/3:x
2)1 2/3:x/4=6:0,3.
3) x-3/x-2=4/7
4) |x|+3,5=0
5)|x+1/3|-4=1
3^x+1 = 9^x
Tìm x biết : a) x+3/22=-27/121.11/9 b) (3và2/20-2và1/20)x+2/7=3/5 c) |3/2x-5|-1/2=-1/4
a) 3^2x-1=243
b) 3^x+1=9^x
c) (4/7-1/2x)^3=-8/34
Tìm các số x, y, z, biết rằng: \(\frac{2x}{3}=\frac{3y}{4}=\frac{4z}{5}\) và -x - y - z = -49