if cotA + cotB + cotC = 0, then prove that ΣtanA)^2 = Σtan^2(A)

[Huratio]

if cotA + cotB + cotC = 0, then prove that (ΣtanA)^2 = Σtan^2(A)
How am I suppose to solve this question?
There's a similar question like
If
If cosecA + cosecB + cosecC =0 then prove that (ΣsinA)^2 = Σsin^2(A)

What the **** am I suppose to do? How do I solve it? I don't even know what is (ΣsinA)^2 or (ΣtanA)^2 equal to.
I only know that Σ this thing is called sigma notation or summation notation and that's just it.
I was solving trigonometry then suddenly they put this question in without explaining what sigma notation is.

 

[stapel]

if cotA + cotB + cotC = 0, then prove that (ΣtanA)^2 = Σtan^2(A)
How am I suppose to solve this question?
There's a similar question like
If cosecA + cosecB + cosecC =0 then prove that (ΣsinA)^2 = Σsin^2(A)

What the **** am I suppose to do? How do I solve it? I don't even know what is (ΣsinA)^2 or (ΣtanA)^2 equal to.
I only know that Σ this thing is called sigma notation or summation notation and that's just it.
I was solving trigonometry then suddenly they put this question in without explaining what sigma notation is.

Have they provided any context? For instance, are A, B, and C the three angles of a triangle? What are the limits of the summation? What is the variable in the terms of the summation (that is, what is the part that is changing from one term to the next)? Thank you!

 

[blamocur]

I don't even know what is (ΣsinA)^2 or (ΣtanA)^2 equal to.

I am in even worse position than you: I have no clue what this notation means.

Where did you get this? Can you post the source as is?

Thank you.

 

[BigBeachBanana]

The problem statement is most likely as follows:

If [imath]\cot(A)+\cot(B)+\cot(C) = 0[/imath], then show that [imath]\left(\tan(A)+\tan(B)+\tan(C)\right)^2 = \tan^2(A)+\tan^2(B)+\tan^2(C)[/imath]

where they might be using the shorthand [imath]\sum \tan(A) =\tan(A)+\tan(B)+\tan(C).[/imath]

 

[khansaheb]

If cot⁡(A)+cot⁡(B)+cot⁡(C)=0

Then first show:

tan(A) * tan(B) + tan(B) * tan(C) + tan(C) * tan(A) = 0

 

[Huratio]

Have they provided any context? For instance, are A, B, and C the three angles of a triangle? What are the limits of the summation? What is the variable in the terms of the summation (that is, what is the part that is changing from one term to

Have they provided any context? For instance, are A, B, and C the three angles of a triangle? What are the limits of the summation? What is the variable in the terms of the summation (that is, what is the part that is changing from one term to the next)? Thank you!

No they didn't. I typed exactly what the question is. It is written in my text book.

 

[Huratio]

I am in even worse position than you: I have no clue what this notation means.

Where did you get this? Can you post the source as is?

Thank you.

I got it from my text book. Here's a picture of it.

 

[Huratio]

The problem statement is most likely as follows:

If [imath]\cot(A)+\cot(B)+\cot(C) = 0[/imath], then show that [imath]\left(\tan(A)+\tan(B)+\tan(C)\right)^2 = \tan^2(A)+\tan^2(B)+\tan^2(C)[/imath]

where they might be using the shorthand [imath]\sum \tan(A) =\tan(A)+\tan(B)+\tan(C).[/imath]

Yesssssssssss. It worked. Thank you so mucb