Question

已知f(x)=x^2-2mx+3,且f(-m)-f(1+m)=3,则m=

Answer 1

f(-m)-f(1+m)=3

(m²+2m²+3)-[(1+m)²-2m(1+m)+3]=3

m²+2m²+3-1-2m-m²+2m+2m²-3=3

4m²=4

m²=1

m=-1,m=1