1.

a, \(^{^2}\left(x-2\right)=9\) b,\(^{^3}\left(3x-1\right)=-8\) c, \(\left(x+\dfrac{1}{2}\right)^2=\dfrac{1}{16}\) d, \(\left(\dfrac{2}{3}\right)^x=\dfrac{4}{9}\) e, \(\left(\dfrac{1}{2}\right)^{x-1}=\dfrac{1}{16}\) f,\(\left(\dfrac{1}{2}\right)^{2x-1}=8\)

2.tìm số tự nhiên n biết

a, \(3^{n-1}=27\) b, \(3^{n-1}=\dfrac{1}{243}\) c, \(\left(\dfrac{1}{2}\right)^{2n-1}=\dfrac{1}{8}\) d, \(\left(-\dfrac{1}{3}\right)^{n-5}=\dfrac{1}{81}\) e,\(2^{-1}.2^n+4.2^n=9.2^5\)

a) \(\dfrac{1}{7}=\dfrac{8}{-x}\)

b) \(\dfrac{3x}{9}=\dfrac{2}{6}\)

c) \(4\dfrac{2}{5}:\left(-\dfrac{33}{10}\right)+x=-1\dfrac{5}{6}\)

d) \(45\%.x-2\dfrac{3}{8}=-1\dfrac{31}{40}\)

Bài 1:tìm x

a)|x-3|+7=x

b)|2x-5|-5=x

Bài 2:tìm cặp số nguyên x,y sao cho:

a)x/9-3/y=18

b)x/7-1/2=1/y+1

các bạn giúp mình nha

mình sẽ tick cho các bạn

thanks trước

tính: \(3\dfrac{1}{7}:\left\{\left[2-1\dfrac{3}{5}:\left(\dfrac{4}{3}-1,6\right)\right]-25\%\right\}\)

tính:

a) \(2\dfrac{3}{4}.\left(-0,4\right)-1\dfrac{3}{5}.2,75+\left(-1,2\right):\dfrac{4}{11}\)

b) \(1,4.\dfrac{15}{49}-\left(\dfrac{4}{5}+\dfrac{2}{3}\right):2\dfrac{1}{5}\)

c) \(\left(-3,2\right).\dfrac{15}{64}+\left(0,8-2\dfrac{4}{15}\right):3\dfrac{2}{3}\)

d) \(0,02.\dfrac{-25}{2}+\dfrac{3}{8}+\left(-2\dfrac{9}{20}\right).\dfrac{2}{7}\)

e) \(34\%:\dfrac{51}{16}-3\dfrac{7}{9}.6,5-\left(0,4\right)^2\)

tính:

a) \(25\%-\dfrac{5}{4}+1\dfrac{5}{6}\)

b) \(75\%:2\dfrac{1}{5}-\left(0,5\right)^2.\left(-7\right)+2,5\left(7\dfrac{2}{3}-5\dfrac{2}{3}\right)\)

c) \(45:2\dfrac{4}{7}+50\%-1,25\)

d) \(350\%:\dfrac{105}{24}+4\dfrac{5}{6}:2-\left(0,5\right)^2.30\%\)

e) \(4\dfrac{2}{5}.0,5-1\dfrac{3}{7}.14\%+\left(-0,8\right)\)

giúp mk với

Tìm một số tự nhiên a nhỏ nhất có 3 chữ số biết rằng khi chia a cho 7 thì dư 3; khi chia a cho 11 thì dư 8.

5^2x-3-2.5^2=5^2.3

a, Tính tổng

A= 1.2+2.3+3.4+...+99.100

Bài 1: Tìm x, y biết :

\(\left|x+123\right|+|\left|y+1\right|-5|=0\)