Toán Lớp 7: (2/3x+1)^4=16 /giúp mikkkkkkkkkkkkkkkkkkkkkk/

Question

Toán Lớp 7:  (2/3x+1)^4=16 /giúp mikkkkkkkkkkkkkkkkkkkkkk/

dongoclandiem · Answer

($ frac{2}{3}$ $x^{}$ + 1 )$^{4}$ = 16     ($ frac{2}{3}$ $x^{}$ + 1 )$^{4}$ = $(2)^{4}$      &rarr;  ( left[  begin{array}{l} frac{2}{3}x=2    frac{2}{3}x=-2 end{array}  right. )     &rarr;  ( left[  begin{array}{l} frac{2}{3}x=2-1   frac{2}{3}x=(-2)-1 end{array}  right. )     &rarr;  ( left[  begin{array}{l} frac{2}{3}x=1    frac{2}{3}x=-3 end{array}  right. )      &rarr;  ( left[  begin{array}{l}x=1: frac{2}{3}   x=(-3): frac{2}{3} end{array}  right. )      &rarr; ( left[  begin{array}{l}x= frac{3}{2}   x= frac{-9}{2}  end{array}  right. )      Vậy $x^{}$ =$ frac{3}{2}$ hoặc  $x^{}$ = -$ frac{9}{2}$

huongtructram · Answer

(2/3 x + 1)^4 = 16   (2/3 x + 1)^4 = (&plusmn;2)^4   => {(2/3 x + 1 = 2),(2/3 x + 1 = -2):}   => {(2/3 x = 1),(2/3 x = -3):}   => {(x = 3/2),(x = -9/2):}   Vậy {(x = 3/2),(x = -9/2):}