已知tan(3π+α)=根号三,α∈﹙0,π/2﹚求值1:cos﹙π+α﹚2:sin﹙3π+α﹚

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已知tan(3π+α)=根号三,α∈﹙0,π/2﹚求值1:cos﹙π+α﹚2:sin﹙3π+α﹚
已知tan(3π+α)=根号三,α∈﹙0,π/2﹚求值
1:cos﹙π+α﹚
2:sin﹙3π+α﹚

已知tan(3π+α)=根号三,α∈﹙0,π/2﹚求值1:cos﹙π+α﹚2:sin﹙3π+α﹚
tan(3π+α)=√3,则tanα=√3 [说明:正切函数的周期是π]
α∈﹙0,π/2﹚
α=π/3
cos﹙π+α﹚
=-cosα
=-cosπ/3
=-1/2
sin﹙3π+α﹚
=-sinα
=-sinπ/3
=-√3 /2

tan(3π+α)=tan(π+α)=sin﹙π+α﹚/cos﹙π+α﹚=sin﹙3π+α﹚/cos﹙π+α﹚
α∈﹙0,π/2﹚
cos﹙π+α﹚<0,sin﹙3π+α﹚<0
cos^2﹙π+α﹚+sin^2﹙3π+α﹚=1
已知tan(3π+α)=根号三
1:cos﹙π+α﹚=-0.5
2:sin﹙3π+α﹚=-0.5根号三

tan(3π+α)=√3
3π+α=π/3+kπ
α∈﹙0,π/2﹚
α=π/3
1、cos(π+π/3)=-1/2
2、sin(3π+π/3)=-√3/2