Prove tan(x)-sin(x)/2tan(x) = sin^2(x/2)

  • Thread starter Elijah the Wood
  • Start date
In summary, the conversation is about two math problems that the person is struggling with. The first problem is to prove the given identity of tan(x)-sin(x)/2tan(x) = sin^2(x/2). The person has made some progress by simplifying one side to 1-sin(x)/2, but is unsure of what to do next. The second problem is to solve the equation sin2x = 1 / tanx + cot2x. The person has tried to simplify the left side to 2sin(x)cos(x) and is unsure of how to continue. They are asking for help with both problems.
  • #1
Elijah the Wood
7
0
I'm retarded...any help would be much congratulated...and i have two problems that are bugging me fiercing

Prove the given identity:

1)
tan(x)-sin(x)/2tan(x) = sin^2(x/2)



2)
sin2x = 1 / tanx + cot2x
 
Last edited:
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  • #2
Please show us what you have tried so far.
 
  • #3
Hmmm..that is tough...
I'm actually having trouble w/ questions similar to this too
 
  • #4
on number 2...wouldn't you try to get both sides equal to "sin2x"?
 
  • #5
1)
tan(x)-sin(x)/2tan(x) = sin^2(x/2)
1-sin(x)/2 = sin^2(x/2)

(That's as far as I've gotten on this one...but i don't know if I'm in the right direction or what to do next?)

2)
sin2x = 1 / tanx + cot2x
2sin(x)cos(x) = ''
sin(x) * cos(x) * sin(x) = ''

(The same from #1 applies to this problem)
 
  • #6
can anyone help?
 

1. What is the given statement?

The given statement is: tan(x)-sin(x)/2tan(x) = sin^2(x/2)

2. What does the symbol "tan" represent?

"tan" represents the trigonometric function tangent, which is equal to the ratio of the opposite side to the adjacent side of a right triangle.

3. How is this statement proven?

This statement can be proven using basic trigonometric identities, such as the double angle formula for sine and the power-reducing formula for cosine.

4. What is the purpose of proving this statement?

Proving this statement can help to understand the relationships between trigonometric functions and to solve more complex trigonometric equations and problems.

5. Are there any restrictions on the values of x for this statement to hold true?

Yes, there are restrictions on the values of x. The statement is only true for values of x where tan(x) and sin(x/2) are defined, which is when x is not equal to odd multiples of pi/2.

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