[질문] 탄젠트135°어떻게구하죠

tan@=sin@/cos@기억해놓으시구요/cos@=a/bsin@=a/ctan@b/c이걸대입하시면식이성립되요/135도는2사분면,좌표x는마이너스y는플러스135-90=45 -1입니다