vá X.y =-12
Bäüd. cho
Tinh gid t ca briă thite -
9, A = x" + 2xy ty
W B = x²+y?
9c= xジt 34-(x+y)+yi
D = x3 ty3.
thoa man : x+y =nd
%3D
1 ty =1. Tinh, gid t biêh thní
M= 3:12'ty) - (だty)
Baiz. cho
Bã3. cho x ty = -3 va x tyt=29. Tin x° ty?
Bün 4
cho -y =5 va x+y"=15. Tnh x3-y3