find all angles between pi and pi satisfying the given condi

find all angles between (-pi) and (pi) satisfying the given condition. answers could be in any order. accurate to 2 decimal places tan(a)=2.4 cos(a)=0.2 sin(a)=-0.1 sec(a)=1.9

Solution

tan a=2.4

a=tan^-1(2.4)

a=67.38 degree , 247.38 degree

cos a = 0.2

a = cos^-10.2

a=78.46 degree, 281.54 degree

sin a =-0.1

a=sin^-1(-0.1)

a= 354.26 degree, 264.26 degree

sec a =1.9

a = sec^-1(1.9)

a= 57.99 degree, 302.01 degree