How do you find the exact value of #tan300#?

2 Answers
Nov 9, 2016

#tan(300^circ)=color(green)(-sqrt(3))#

Explanation:

#300^circ# is equivalent to #(-60^circ)#
A #60^circ# right triangle is one of the standard triangles.
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#tan = "opposite"/"adjacent"#

Nov 9, 2016

#tan(300^@) = -sqrt(3)#

Explanation:

#300^@=360^@-60^@# equivalently we have
#2pi-pi/3 = 300^@/180^@ pi# then
#tan(300^@)=tan(2pi-pi/3)# but #tan# is periodic with period #pi# so
#tan(2pi-pi/3)=tan(-pi/3)# and #tan# is an odd function so
#tan(-pi/3)=-tan(pi/3)#
Now #tan(x)=sin(x)/cos(x)# and #sin(pi/3)=1/2# so
#cos(x)=sqrt(1-cos^2(x)) = sqrt(1-1/4)=sqrt(3)/2#

Finally

#tan(300^@) = -sqrt(3)#