Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 9: 1,Giải các phương trình sau: a, √(3x-1) ² =6 b,( √x +1)² – 2√x ( √x -2) =7-x

Toán Lớp 9: 1,Giải các phương trình sau: a, √(3x-1) ² =6 b,( √x +1)² – 2√x ( √x -2) =7-x

Comments ( 1 )

  1.  a,$\sqrt[]{(3x-1)²}$ =6
    ⇔|3x-1|=6
    \(\left[ \begin{array}{l}3x-1=6 <=> x=7/3\\3x-1 = -6<=> x=-5/3\end{array} \right.\)
     Vậy S={7/3;-5/3}
    b,($\sqrt[]{x}$ +1)²-2$\sqrt[]{x}$ ($\sqrt[]{x}$ -2=7-x
    ĐKXĐ:x≥0
    ⇔x+2$\sqrt[]{x}$ +1-2x+4$\sqrt[]{x}$ -7+x=0
    ⇔6$\sqrt[]{x}$ -6=0
    ⇔$\sqrt[]{x}$ =1
    ⇔x=1(T/m)
     Vậy S={1}
     

Leave a reply

222-9+11+12:2*14+14 = ? ( )