已知f(x)满足2f(x)+f(-x)=-3x+1,求f(x)

问题描述:

已知f(x)满足2f(x)+f(-x)=-3x+1,求f(x)

2f(x)+f(-x)=-3x+1
则2f(-x)+f(x)=3x+1.....①
4f(x)+2f(-x)=-6x+2.....②
②式-①式得
3f(x)=-9x+1
f(x)=-3x+1/3

令x=a,得2f(a)+f(-a)=-3a+1...①
令x=-a,得2f(-a)+f(a)=3a+1.②
由①-②得:f(a)-f(-a)=-6a.③
由①+③得:3f(a)=-9a+1
f(a)=-3a+1/3
令a=x,得f(x)=-3x+1/3
故f(x)的解析式为f(x)=-3x+1/3