Question

困扰我好久的数学题,求解.[tan(x/2)+1]/[1-tan(x/2)] + [tan(x/2)-1]/[1+tan

Answer 1

[tan(x/2)+1]/[1-tan(x/2)] + [tan(x/2)-1]/[1+tan(x/2)]

[(tan(x/2)+1)^2 + (tan(x/2)-1)（1-tan(x/2)）]/[1-(tan(x/2))^2]

[(tan(x/2)+1)^2 - (tan(x/2)-1)^2]/[1-(tan(x/2))^2]

这样子看懂了没