Question

AX +BY =A方+2AB-B方 BX+AY =A方+B方 解方程

Answer 1

AX + BY = A^2 + 2AB - B^2 (1)BX + AY = A^2 + B^2 (2) (1)+(2):(A+B)X + (B+A)Y = 2A^2 + 2AB (A+B)(X+Y) = 2A(A+B)X+Y = 2AY = 2A-X(2) ==> BX + A(2A-X) = A^2 + B^2(B-A)X = A^2 + B^2 - 2A^2 = (B-A)(B+A) X =...