g(x)周期為1,因此有g(shù)(x+1)=g(x)
f(x+1)=(x+1)+g(x+1)
=x+g(x)+1
=f(x)+1
同理,
f(x+2)=f(x+1)+1
=>f(x+2)=f(x)+2
當(dāng)0<=x<=1時,-2<=f(x)<=5
=>-1<=f(x)+1<=6
=>-1<=f(x+1)<=6 ,則1<=x<=2時,-1<=f(x)<=6
=>0<=f(x+2)<=7,則2<=x<=3時,0<=f(x)<=7
因此有0<=x<=3時,-2<=f(x)<=7
所以f(x)的值域是[-2,7]