solve the equation for x in the interval 02pi Use exact solu
solve the equation for x in the interval [0,2pi). Use exact solutions where possible and give approximate solutions correct to four decimal places
3tan^2x+5tanx+2=0
Solution
3tan^2x+5tanx+2=0 interval [0,2pi)
Factorise : 3tan^2x+5tanx+2
3tan^2x +3tanx +2tanx +2 =0
3tanx( tanx +1) +2(tanx +1) =0
(3tanx +2)( tanx +1) =0
3tanx +2 =0
tanx = -2/3
x = pi - 0.5880 = 2.5535 rad
x = 2pi - 0.5880 = 5.6951 rad
tanx +1 =0
x = pi -pi/4 , 2pi -pi/4
= 3pi/4 , 7pi/4 = 2.3561 , 5.4977
Solution : x = 2.3561 , 2.5535 , 5.4977 , 5.6951,
