Question #82a02

2 Answers
Oct 7, 2017

Here X= #Tan^-1((1-(3)^(1/2)]/(1+(3)^(1/2)))#

Explanation:

There is an identity #Tan(x+y)# = #(Tan(x)+tan(y))/(1-tan(x)tan(y)#

When we apply it to your equation we get
#tan(x+60)=(tan(x)+tan(60))/(1-tan(x)tan(60)#
As we know #tan(60)=(3)^(1/2)#

Therefore #(tan(x)+(3)^(1/2))/(1-(3)^(1/2)tanx)=1#

#tan(x)+(3)^(1/2)=1-(3)^(1/2)tan(x)#

#tan(x)+(3)^(1/2)tan(x)=1-(3)^(1/2)#

#tan(x)(1+(3)^(1/2))=1-(3)^(1/2)#

#tan(x)=(1-(3)^(1/2))/(1+(3)^(1/2)#

Therefore #x=tan^-1((1-(3)^(1/2))/(1+(3)^(1/2)))#

Oct 7, 2017

A different approach...
See the answer below...

Explanation:

#tan(x+60)=1#
#=>tan(x+60)=tan45#(mainly)

We might take further higher value...
#x+60=45#
#=>x=-15#

Hope this helps...

It is same as #tan^-1((1-sqrt3)/(1+sqrt3))#...