tanx=1/2
tan2x=2tanx/(1-tan²x)=4/3
sinx/cosx=tanx=1/2
cosx=2sinx
sin²x+cos²x=1
所以sinx=√5/5
cosx=2√5/5
sin2x=2sinxcosx=4/5
cos2x=cos²x-sin²x=3/5
所以sin(2x+π/3)
=sin2xcosπ/3+cos2xsinπ/3
=(4+3√3)/10
tanx=1/2
tan2x=2tanx/(1-tan²x)=4/3
sinx/cosx=tanx=1/2
cosx=2sinx
sin²x+cos²x=1
所以sinx=√5/5
cosx=2√5/5
sin2x=2sinxcosx=4/5
cos2x=cos²x-sin²x=3/5
所以sin(2x+π/3)
=sin2xcosπ/3+cos2xsinπ/3
=(4+3√3)/10