问题补充:
已知sina+cosa=根号3/2,则tana+cota=
答案:
(sina+cosa)^2=sin^2a+cos^2a+2sinacosa=1+2sinacosa=3/4
∴sinacosa=-1/8
tana+cota=sina/cosa+cosa/sina=(sin^2a+cos^2a)/sinacosa=1/sinacosa=-8
时间:2020-01-15 13:43:50
已知sina+cosa=根号3/2,则tana+cota=
(sina+cosa)^2=sin^2a+cos^2a+2sinacosa=1+2sinacosa=3/4
∴sinacosa=-1/8
tana+cota=sina/cosa+cosa/sina=(sin^2a+cos^2a)/sinacosa=1/sinacosa=-8