化简sin(a-π)cot(a-2π)/cos(a-π)tan(a-2π)答案是cota,我做出来是-cota 求解!_数学解答

化简sin(a-π)cot(a-2π)/cos(a-π)tan(a-2π)
答案是cota,我做出来是-cota 求解!

人气：112 ℃　时间：2020-03-28 10:29:14

解答

sin(a-π)cot(a-2π)/cos(a-π)tan(a-2π)
=-[sin(π-a)cota]/[cos(π-a)tana]
=-[sina*cota]/-[cosatana]
=cosa/sina
=cota