证明行列式
|xyx+y|
|yx+yx|
|x+yxy|
=-2(x3+y2)
证明： |x y x+y| |y x+y x| |x+Y x y| = |2x+2y y x+y| |2x+2y x+y x| |2x+2y x y| =2(x+y) |1 y x+y| |1 x+y x| |1 x y| =2(x+y) |1 y x+y| |0 x -y| |0 x-y -x| =2(x+y)(-x2+xy-y2) =-2(x3+y3)
证明行列式
|xyx+y|
|yx+yx|
|x+yxy|
=-2(x3+y2)
证明： |x y x+y| |y x+y x| |x+Y x y| = |2x+2y y x+y| |2x+2y x+y x| |2x+2y x y| =2(x+y) |1 y x+y| |1 x+y x| |1 x y| =2(x+y) |1 y x+y| |0 x -y| |0 x-y -x| =2(x+y)(-x2+xy-y2) =-2(x3+y3)
