Question

REZOLVAŢI ECUAȚIILE: a) (2x+1) la a 2=81; b) (3x-1) la a 2=121 ; c) 3(x-3) la a 2=48 ; d) 5(x+2) la a 2=45; . e) 7(2x-1) la a 2 = 175 Repede

Answer 1

c)

$\it3(x-3)^2 = 48|_{:3} \Leftrightarrow (x-3)^2 = 16 \Leftrightarrow \sqrt{(x-3)^2} =\sqrt{16}$

$\it \Leftrightarrow |x-3| =4 \Leftrightarrow x-3 = \pm4$

$I)\ \it x -3 = -4 \Leftrightarrow x = -4+3 \Leftrightarrow\ x = -1$

$\Leftrightarrow \it x-3 = 4 \Leftrightarrow x=4+3 \Leftrightarrow x = 7\ .$

$S = \{-1,\ 7\}\ .$