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( √ ( 3X - 1) + √ ( 6X + 2 ) ) ^2 = ( √ 9X + 1 )^2
3X - 1 + 2 √ ( 3X -1)*( 6X + 2) = 9X + 1
2 √ ( 3X - 1 )*( 6X + 2 ) = 6X + 2
( √ (3X - 1)*( 6X + 2 ) ) ^2 = ( 3X + 1 )^2
( 3X - 1)*( 6X + 2 ) = 9X^2 + 6X + 1
18X^2 + 6X - 6X - 2 = 9X^2 + 6X + 1
9X^2 - 6X - 3 = 0
3 *( X^2 - 2X - 1 ) = 0
D = 4 + 4 = 8 ; √ D = 2 √ 2
X1 = ( 2 + 2 √ 2 ) : 2 = ( 1 + √ 2 )
X2 = ( 1 - √ 2 )