Bài 2:
a. 1$\frac{1}{2}$x + 1 = $\frac{5}{6}$
$\frac{3}{2}$x = $\frac{5}{6}$ - 1
$\frac{3}{2}$x = $\frac{5}{6}$ - $\frac{6}{6}$
$\frac{3}{2}$x = $\frac{-1}{6}$
x = $\frac{-1}{6}$ : $\frac{3}{2}$
x = $\frac{-1}{6}$ . $\frac{2}{3}$
x = $\frac{-1}{3}$ . $\frac{1}{3}$
x = $\frac{-1}{9}$
b. $\frac{3}{4}$x - 1$\frac{1}{2}$ = $\frac{3}{4}$
$\frac{3}{4}$x - $\frac{3}{2}$ = $\frac{3}{4}$
$\frac{3}{4}$x = $\frac{3}{4}$ + $\frac{3}{2}$
$\frac{3}{4}$x = $\frac{3}{4}$ + $\frac{6}{4}$
$\frac{3}{4}$x = $\frac{9}{4}$
x = $\frac{9}{4}$ : $\frac{3}{4}$
x = $\frac{9}{4}$.$\frac{4}{3}$
x = $\frac{3}{1}$.$\frac{1}{1}$
x = 3
c. -$\frac{2}{3}$x + 1 = $(\frac{-2}{3})^{2}$
$\frac{-2}{3}$x + 1 = $\frac{4}{9}$
$\frac{-2}{3}$x = $\frac{4}{9}$ - 1
$\frac{-2}{3}$x = $\frac{4}{9}$ - $\frac{9}{9}$
$\frac{-2}{3}$x = $\frac{-5}{9}$
x = $\frac{-5}{9}$ : $\frac{-2}{3}$
x = $\frac{-5}{9}$.$\frac{-3}{2}$
x = $\frac{-5}{3}$.$\frac{-1}{2}$
x = $\frac{5}{6}$
d. $x^{2}$ = $\frac{4}{9}$
⇒ $x^{2}$ = $(\frac{2}{3})^{2}$ = $(\frac{-2}{3})^{2}$
⇒ x = $\frac{2}{3}$ hay x = $\frac{-2}{3}$
e. $(\frac{2}{3}$x - $\frac{1}{2})^{2}$ - 1 = $\frac{9}{16}$
$(\frac{2}{3}$x - $\frac{1}{2})^{2}$ = $\frac{9}{16}$ + 1
$(\frac{2}{3}$x - $\frac{1}{2})^{2}$ = $\frac{9}{16}$ + $\frac{16}{16}$
$(\frac{2}{3}$x - $\frac{1}{2})^{2}$ = $\frac{25}{16}$
$(\frac{2}{3}$x - $\frac{1}{2})^{2}$ = ($\frac{5}{4})^{2}$ = ($\frac{-5}{4})^{2}$
TH1: $\frac{2}{3}$x - $\frac{1}{2}$ = $\frac{5}{4}$
$\frac{2}{3}$x = $\frac{5}{4}$ + $\frac{1}{2}$
$\frac{2}{3}$x = $\frac{5}{4}$ + $\frac{2}{4}$
$\frac{2}{3}$x = $\frac{7}{4}$
x = $\frac{7}{4}$ : $\frac{2}{3}$
x = $\frac{7}{4}$.$\frac{3}{2}$
x = $\frac{21}{8}$
TH2: $\frac{2}{3}$x - $\frac{1}{2}$ = $\frac{-5}{4}$
$\frac{2}{3}$x = $\frac{-5}{4}$ + $\frac{1}{2}$
$\frac{2}{3}$x = $\frac{-5}{4}$ + $\frac{2}{4}$
$\frac{2}{3}$x = $\frac{-3}{4}$
x = $\frac{-3}{4}$ : $\frac{2}{3}$
x = $\frac{-3}{4}$.$\frac{3}{2}$
x = $\frac{-9}{8}$
