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Don't understand this question

I'm completely stuck on this question.
I've got cot = -1/sqrt(3) so far but have no idea where to go from here.
It's Question B
Original post by xxVENUSx
I'm completely stuck on this question.
I've got cot = -1/sqrt(3) so far but have no idea where to go from here.
It's Question B

Take reciprocal of both sides. You get tan on the left then.
Reply 2
Original post by RDKGames
Take reciprocal of both sides. You get tan on the left then.

You mean 1/tan(x)=-sqrt(3)?
Original post by xxVENUSx
You mean 1/tan(x)=-sqrt(3)?

why 1/tan(x)?

Reciprocal of cot(x) is just tan(x). Use the sine and cosine definitions of cot and tan to see this.
Reply 4
Original post by RDKGames
why 1/tan(x)?

Reciprocal of cot(x) is just tan(x). Use the sine and cosine definitions of cot and tan to see this.

I'm completely lost. I've been trying to use cot(x)=1/tan x. I just don't understand what this means at all.
Original post by xxVENUSx
I'm completely lost. I've been trying to use cot(x)=1/tan x. I just don't understand what this means at all.

It is an identity. A bit like how cos^2(x) + sin^2(x) is the same as 1. Replacing cot(x) with 1/tan(x) does not change the equation whatsoever, therefore it is important to use it.

cot(x) = - 1/rt(3)

means

1/tan(x) = - 1/rt(3)

which means

tan(x) = - rt(3)

and this is something you can proceed to solve as normal.
Reply 6
Original post by RDKGames
It is an identity. A bit like how cos^2(x) + sin^2(x) is the same as 1. Replacing cot(x) with 1/tan(x) does not change the equation whatsoever, therefore it is important to use it.

cot(x) = - 1/rt(3)

means

1/tan(x) = - 1/rt(3)

which means

tan(x) = - rt(3)

and this is something you can proceed to solve as normal.

I got that but can't get to the answer (2pi/3)
Original post by xxVENUSx
I got that but can't get to the answer (2pi/3)

Tan has a period of pi radians. Use this fact.
Reply 8
Can someone just work through the whole question. I just need the full answer and how to do it.
Reply 9
I really need help with this
Original post by xxVENUSx
I really need help with this

Add pi to your answer that you get from

tan(x) = -sqrt(3)

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