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Statement I tan alpha+2tan 2 alpha+4 ta...

Statement I `tan alpha+2tan 2 alpha+4 tan 4 alpha + 8 tan 8 alpha+16 cot 16 alpha=cot alpha`
Statement II `cot alpha- tan alpha=2 cot 2 alpha`

A

Both Statement I and Statement II are individually true and R is the correct explanation of Statement I.

B

Both Statement I and Statement II are individually true but Statement II is not the correct explanaton of Statement I.

C

Statement I is true but Statement II is false.

D

Statement I is false but Statement II is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given statements, we will analyze each statement step by step. ### Step 1: Analyze Statement I We need to prove that: \[ \tan \alpha + 2 \tan 2\alpha + 4 \tan 4\alpha + 8 \tan 8\alpha + 16 \cot 16\alpha = \cot \alpha \] ### Step 2: Rewrite Cotangent We know that: \[ \cot 16\alpha = \frac{1}{\tan 16\alpha} \] Thus, we can rewrite the equation as: \[ \tan \alpha + 2 \tan 2\alpha + 4 \tan 4\alpha + 8 \tan 8\alpha + \frac{16}{\tan 16\alpha} = \cot \alpha \] ### Step 3: Use the Identity for Cotangent Using the identity for cotangent: \[ \cot \alpha = \frac{\cos \alpha}{\sin \alpha} \] We can express \( \cot \alpha \) in terms of \( \tan \alpha \): \[ \cot \alpha = \frac{1}{\tan \alpha} \] ### Step 4: Analyze Statement II We need to prove that: \[ \cot \alpha - \tan \alpha = 2 \cot 2\alpha \] ### Step 5: Rewrite Cotangent for 2α Using the double angle formula for cotangent: \[ \cot 2\alpha = \frac{\cot^2 \alpha - 1}{2 \cot \alpha} \] Thus: \[ 2 \cot 2\alpha = \frac{2(\cot^2 \alpha - 1)}{2 \cot \alpha} = \frac{\cot^2 \alpha - 1}{\cot \alpha} \] ### Step 6: Substitute in Statement II Substituting \( 2 \cot 2\alpha \) back into Statement II gives: \[ \cot \alpha - \tan \alpha = \frac{\cot^2 \alpha - 1}{\cot \alpha} \] ### Step 7: Verify the Equality To verify the equality: 1. Rewrite \( \tan \alpha \) as \( \frac{1}{\cot \alpha} \). 2. Substitute into the equation: \[ \cot \alpha - \frac{1}{\cot \alpha} = \frac{\cot^2 \alpha - 1}{\cot \alpha} \] ### Step 8: Simplify Multiply through by \( \cot \alpha \): \[ \cot^2 \alpha - 1 = \cot^2 \alpha - 1 \] This confirms that Statement II is true. ### Conclusion Both statements are true, and Statement II serves as a valid explanation for Statement I.
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tan alpha+2tan2 alpha+4tan4 alpha+8cot8 alpha=cot alpha

Prove that tan alpha + 2tan 2alpha + 4tan 4alpha + 8cot 8alpha = cot alpha .

Knowledge Check

  • tan alpha + 2tan 2alpha + 4tan 4alpha + 8tan 8alpha is equal to :

    A
    tan 16 `alpha`
    B
    0
    C
    `cot alpha`
    D
    none of these
  • tan alpha+2tan2alpha+4tan4alpha+8cot8alpha is equal to

    A
    `tan16alpha`
    B
    0
    C
    `cot alpha`
    D
    none of these
  • tanalpha+2tan2alpha+4tan4alpha+8cot8alpha=?

    A
    `tanalpha`
    B
    `tan2alpha`
    C
    `cotalpha`
    D
    `cot2alpha`
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    Prove that: tan alpha+2tan2 alpha+4tan4 alpha+8cot8 alpha=cot alpha

    If tan alpha+cot alpha=2 then

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