∵ tana=(m²-1)/(2m)，0∴ tana<0，∴ π/2sec²a=tan²a+1=(m²-1)²/(2m)²+1=(m²+1)²/(2m)²cosa=1/seca=-1/√sec²a=-2m/(m²+1)
∴ tana<0，∴ π/2sec²a=tan²a+1=(m²-1)²/(2m)²+1=(m²+1)²/(2m)²cosa=1/seca=-1/√sec²a=-2m/(m²+1)
sec²a=tan²a+1=(m²-1)²/(2m)²+1=(m²+1)²/(2m)²
cosa=1/seca=-1/√sec²a=-2m/(m²+1)
如本站内容“对您有用”，欢迎随意打赏，让我们持续更新！
