有两个有理数a、b(b≠0),规定一种新的运算“*”: a*b=a+ 1 b .例如...
发布网友
发布时间:2024-05-15 14:22
我来回答
共1个回答
热心网友
时间:2024-05-27 08:57
(1)①3*5=3+ 1 5 = 16 5 ;
②-4*3=-4+ 1 3 =- 11 3 ;
③(1*2)*3
=(1+ 1 2 )*3
= 3 2 + 1 3
= 11 6 ;
④1*(2*3)
=1*(2+ 1 3 )
=1* 7 3
=1+ 3 7
= 10 7 ;
(2)①(m*n)*x
=(m+ 1 n )*x
= mn+1 n *x
= mn+1 n + 1 x
= mnx+x+n nx ,
m*(n*x);
=m*(n+ 1 x )
=m* nx+1 x
=m+ nx+1 x
= mx+nx+1 x ;
故“*”运算不满足(m*n)*x=m*(n*x);
②m+ 1 n =n+ 1 m ,
(m-n)+ 1 n - 1 m =0,
(m-n)+ m-n mn =0,
(mn+1)(m-n) mn =0,
故当m=n≠0或mn=-1时,满足m*n=n*m.