sin25π/4+cos25π/3+tan(-25π/4)=

问题描述:

sin25π/4+cos25π/3+tan(-25π/4)=

=sinπ/4+cosπ/3+tan(-π/4)
=根号2/2+1/2-1
=根号2/2-1/2

原式= sin(6π+π/4)+cos(8π+π/3)+tan(-6π-π/4)
=sinπ/4+cosπ/3-tanπ/4
=√2/2+1/2-1
=(√2-1)/2