化简:1/(tg3a-tga)-1/(ctg3a-ctga)
问题描述:
化简:1/(tg3a-tga)-1/(ctg3a-ctga)
答
1/(tg3a-tga)-1/(ctg3a-ctga)
=1/(tg3a-tga)+tg3a*tga/(tg3a-tga)
=(1+tg3a*tga)/(tg3a-tga)
=(1+tg3a*tga)/[tg(3a-a)*(1+tg3a*tga)]
=ctg2a