已知Ia/bI小于等于1,a不等于0,求tan(π/4+1/2arccosa/b)+tan(π/4-1/2arccosa/b)的值
问题描述:
已知Ia/bI小于等于1,a不等于0,求tan(π/4+1/2arccosa/b)+tan(π/4-1/2arccosa/b)的值
答
为了描述方便,记 x = π/4+1/2arccosa/b , y = π/4-1/2arccosa/b注意到 x+y = π/2则:原式 = tanx + tan(π/2-x) = tanx + cotx= sinx/cosx + cosx/sinx= 1/(sinxcosx)= 1/(0.5sin2x)= 2/sin2x由于 2x =π/2...