函数f(x)=arcsin(sinx)可以用分段函数表示吗
1个回答

f(x)=arcsin(sinx)

当x∈[-π/2,π/2]时,

arcsin(sinx)=x

当x∈(π/2,3π/2]时,

π-x∈[-π/2,π/2)

sinx=sin(π-x)

∴arcsin(sinx)=π-x

当x∈[2kπ-π/2,2kπ+π/2],k∈Z

x-2kπ∈[-π/2,π/2],k∈Z

∴arcsin(sinx)=x-2kπ,

当x∈(2kπ+π/2,2kπ+3π/2],k∈Z

(2k+1)π-x∈[-π/2,π/2)

arcsin(sinx)=(2k+1)π-x

f(x)={ x-2kπ, x∈[2kπ-π/2,2kπ+π/2],k∈Z

{(2k+1)π-x, x∈(2kπ+π/2,2kπ+3π/2],k∈Z