Question

(救命啊)a+b=3,a*b=1,求(a-b)^2-3(a-b)^4+70

Answer 1

a+b=3;

a*b=1;

(a-b)^2=(a+b)^2-4a*b=5

带入表达式得：

(a-b)^2-3(a-b)^4+70

=5-3*25+70

=0