Question

已知x+1分之A+x-1分之B等于x+1乘x-1分之x-3求A.B的值

Answer 1

x+1分之A+x-1分之B等于x+1乘x-1分之x-3；
A(x-1)+B(x+1)=x-3;
A+B=1;
B-A=-3;
2B=-2;
B=-1;
A=2;