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If tan(1/2x) = cosec(x) - sin(x), prove that (tan(1/2x))² = -2 ±√5.

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Final answer:

The question asks for a mathematical proof involving trigonometric identities to demonstrate that (tan(1/2x))² equals -2 ±√5, given tan(1/2x) = cosec(x) - sin(x). Trigonometric identities such as the Pythagorean identity, definitions of trigonometric functions, and double-angle formulas are pivotal for the proof.

Step-by-step explanation:

The question presented involves trigonometric identities and a proof within the subject of mathematics. The student is asked to prove that given tan(1/2x) = cosec(x) - sin(x), it follows that (tan(1/2x))² = -2 ±√5. The key to solving such proof is to manipulate the given equation using known trigonometric identities and eventually arrive at the desired formula.

Some notable identities that can help with this proof are:

  • The Pythagorean identity: sin²(x) + cos²(x) = 1
  • The definition of cosecant in terms of sine: cosec(x) = 1/sin(x)
  • The double angle formulas for sine and cosine, for instance: sin(2x) = 2sin(x)cos(x) and cos(2x) = cos²(x) - sin²(x)

After simplifying the given equation with these identities and performing algebraic manipulations, you may eventually find that the squared function of tan(1/2x) simplifies to a quadratic form, which could potentially lead to the result of -2 ±√5.

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