(1)减数是782,那么被减数就是792,运算的结果就是79+78=157;
792-782=157;
(2)被减数是 n2,那么减数就是(n-1)2;
运算结果是:
n+(n-1)=n+n-1=2n-1;即:
n2-(n-1)2=2n-1.
故答案为:79,157,n-1,2n-1.
(1)减数是782,那么被减数就是792,运算的结果就是79+78=157;
792-782=157;
(2)被减数是 n2,那么减数就是(n-1)2;
运算结果是:
n+(n-1)=n+n-1=2n-1;即:
n2-(n-1)2=2n-1.
故答案为:79,157,n-1,2n-1.