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

Toán Lớp 9: căn (x+căn(x^2-1))+căn(x-căn(x^2-1))=2

Toán Lớp 9: căn (x+căn(x^2-1))+căn(x-căn(x^2-1))=2

Comments ( 1 )

  1. Điều kiện xác định \(\left[ \begin{array}{l}x\ge 1\\x\le-1\end{array} \right.\) 
    $\begin{array}{l} \sqrt {x + \sqrt {{x^2} – 1} }  + \sqrt {x – \sqrt {{x^2} – 1} }  = 2\\  \Leftrightarrow x + \sqrt {{x^2} – 1}  + x – \sqrt {{x^2} – 1}  + 2\sqrt {\left( {x + \sqrt {{x^2} – 1} } \right)\left( {x – \sqrt {{x^2} – 1} } \right)}  = 4\\  \Leftrightarrow 2x + 2\sqrt {{x^2} – \left( {{x^2} – 1} \right)}  = 4\\  \Leftrightarrow 2x + 2\sqrt 1  = 4\\  \Leftrightarrow 2x = 2\\  \Leftrightarrow x = 1 \end{array}$
    $S = \left\{ 1 \right\}$
     

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