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问题: 数学题,在线等

(1)已知定义在R上的奇函数f(x)满足:对于任意实数x属于R,若f(1)=2,有f(x+3)=-f(x),则f(5)=
(2)函数f(x)对于任意实数x满足条件f(x+2)=1/f(x),若f(1)=-5,则f(f(5))=
要详细过程,谢谢


解答:

f(x+3)=-f(x),则f(x+6)=f(x+3+3)= -f(x+3)=f(x)


f(5)= - f(-5) =- f(-5+6)= - f(1) = -2



f(x+2)=1/f(x) ==>f(x+4)=1/f(x+2) =f(x)
f(5)=f(1)=-5

f(f(5))= f(-5)=f(-1)
f(1)=1/f(-1) ==>f(-1)= -1/5

==>f(f(5))= -1/5