tan3 and cos0 Which of the following can be the angle Soluti

tan()=3 and cos()>0. Which of the following can be the angle ?

Solution

tan()=3 <0

cos()>0

so lies in fourth quadrant

least positive value of is 5_/3 radians or 300^o

general solution is =2n -(_/3) where n is an integer

few solutions are =-(13_/3),-(7_/3),-(_/3),(5_/3),(11_/3),(17_/3) or -780^o,-420^o,-60^o,300^o,660^o,960^o