f(x)=arcsinx,求f(0),
sin0=0
f(0)=0
f(1/2)
sinπ/6=1/2
所以
f(1/2)=π/6
,f(-1)
sin(-π/2)=-1
所以
f(-1)=-π/2
f(-根号3/2)
sin(-π/3)=-根号3/2
所以
f(-根号3/2)=-π/3π，怎么写？没有，-π/2<=arcsinx<=π/2