已知tan(π+α)=1/3 三角函数~
问题描述：
已知tan(π+α)=1/3 三角函数~
已知tan(π+α)=1/3,求1/cos(-α)+sin(-α-90度)
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1/sin(540度-α)-cos(-α-270) 的值
1/cos(-α)+sin(-α-90度)/1/cos(-α)+sin(-α-90度)
答
tan(π+α) = tan(α) = 1/3原式=1/cos(-α)+sin(-α-90度) * (sin(540度-α)-cos(-α-270))=(sin(540度-α)-cos(-α-270)) / (cos(-α)+sin(-α-90度))= (sin(α)+sin(α)) / (cos(α)+cos(α))= sin(α)/cos(α) =...