How to solve this equation? The topic is Radian Measure of Angle size.

Solve the equation for 0 ≤ x ≤ 2π.enter image source here

2 Answers
Jul 25, 2018

x=pi/3, (4pi)/3,(3pi)/4, (7pi)/4x=π3,4π3,3π4,7π4

Explanation:

tan^2x+tanx=sqrt3 tanx+sqrt3tan2x+tanx=3tanx+3

tan^2x+tanx-sqrt3tanx-sqrt3=0tan2x+tanx3tanx3=0

tanx(tanx+1)-sqrt3(tanx+1)=0tanx(tanx+1)3(tanx+1)=0

(tanx-sqrt3)(tanx+1)=0(tanx3)(tanx+1)=0

tanx-sqrt3=0tanx3=0 or tanx+1=0tanx+1=0

tanx-sqrt3=0tanx3=0
tanx=sqrt3tanx=3
x=pi/3, pi+pi/3x=π3,π+π3 --> tan xtanx is positive in the first and third quadrant
x=pi/3, (4pi)/3x=π3,4π3


tanx+1=0tanx+1=0
tanx=-1tanx=1
x=pi-pi/4, 2pi-pi/4x=ππ4,2ππ4 --> tanxtanx is negative in the second and fourth quadrant
x=(3pi)/4, (7pi)/4x=3π4,7π4

Jul 25, 2018

pi/3, (3 pi)/4, (4 pi)/3, (7 pi)/4π3,3π4,4π3,7π4

Explanation:

Given: tan^2 x + tan x = sqrt(3) tan x + sqrt(3)," in "[0, 2 pi]tan2x+tanx=3tanx+3, in [0,2π]

Rearrange the equation to be = 0=0:

tan^2 x + tan x - sqrt(3) tan x - sqrt(3) = 0tan2x+tanx3tanx3=0

Group factor:

(tan^2 x + tan x) + (- sqrt(3) tan x - sqrt(3)) = 0(tan2x+tanx)+(3tanx3)=0

tan x ( tan x + 1) -sqrt(3) (tan x + 1) = 0tanx(tanx+1)3(tanx+1)=0

(tan x + 1)(tan x - sqrt(3)) = 0(tanx+1)(tanx3)=0

tan x = -1; " "tan x = sqrt(3)tanx=1; tanx=3

The tangent is positive in quadrants I, III and negative in quadrants II & IV.

x = (3 pi)/4, (7 pi)/4; " " x = pi/3, (4 pi)/3x=3π4,7π4; x=π3,4π3