Solve the equation?

Solve

tanx-sqrt3=0tanx3=0
,
xxin(-pi,-pi/2)uu(-pi/2,pi/2)uu(pi/2,pi)(π,π2)(π2,π2)(π2,π)

2 Answers
Apr 9, 2018

x=pi/3x=π3 or x=-(2pi)/3x=2π3

Explanation:

tan(x)-sqrt(3)=0tan(x)3=0
color(white)("XXX")rarr tan(x)=sqrt(3)XXXtan(x)=3

In Quadrant I, this is one of the standard triangles:
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Using the CAST notation for the Quadrants, a reference angle in Quadrant III will have the same tan(x)tan(x) value i.e. (-pi+pi/3)(π+π3) will have the same value.
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Apr 9, 2018

x = pi/3 + kpix=π3+kπ

Explanation:

tan x = sqrt3tanx=3
Trig table and unit circle give 2 solutions:
x = pi/3x=π3 and x = pi/3 + pi = (4pi)/3x=π3+π=4π3
General answer:
x = pi/3 + kpix=π3+kπ
Inside the interval (-pi, -pi/2)(π,π2), the answer is (4pi)/34π3
Inside the interval (- pi/2, pi/2)(π2,π2), the answer is (pi/3)(π3)
No answer in the interval (pi/2, pi)(π2,π)