q(x1)(2(x1) P (X,) q(x2)q2(x2) A=[④12Φ2…①n q(xn)q2(xn)…9n(xmn V1 1 b r12=∑p2=∑[y-f(x)2=b-Ax l 称方程组Ax=b为超定方程组1 1 2 1 1 1 2 2 2 2 1 2 1 2 ( ) ( ) ( ) ( ) ( ) ( ) [ , , , ] ( ) ( ) ( ) n n n m m n m x x x x x x A x x x              =    =         1 1 1 2 2 2 , , m m n y c y c b r x y c                = = =                         2 2 2 2 2 2 1 1 || || [ ( )] || || m m i i i i i r y f x b Ax  = = = = − = −   称方程组Ax=b为超定方程组