What is the ratio of sin 5x to sin x in this Trigonometric Challenge?

In summary, the Trigonometric Challenge is a mathematical problem-solving game that uses trigonometric functions to solve puzzles and challenges. It can be played by anyone with a basic understanding of trigonometry and can be found online or purchased from educational stores. Playing the Trigonometric Challenge can improve problem-solving skills, strengthen understanding of trigonometric functions, and enhance mathematical reasoning abilities.
  • #1
anemone
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Given that \(\displaystyle \frac{\sin 3x}{\sin x}=\frac{6}{5}\), what is the ratio of \(\displaystyle \frac{\sin 5x}{\sin x}\)?
 
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  • #2
anemone said:
Given that \(\displaystyle \frac{\sin 3x}{\sin x}=\frac{6}{5}\), what is the ratio of \(\displaystyle \frac{\sin 5x}{\sin x}\)?

$\frac{\sin\, 3x}{\sin\, x}=\frac{6}{5}$ given
subtract 1 from both sides
$\frac{\sin\, 3x - \sin\, x}{\sin\, x}=\frac{1}{5}$
or $\frac{2 \sin\, x \cos\, 2x}{\sin\, x}=\frac{1}{5}$
or $\cos \, 2x = \frac{1}{10}\cdots(1)$
now
$\frac{\sin\, 5x + \sin \,x }{\sin x} = \frac{2 \sin\,3x \cos \,2x }{\sin x}$
$=2 \cos \,2x \frac{\sin\,3x}{\sin x}$
$=2 * \frac{1}{10} * \frac{6}{5} = \frac{6}{25}$
hence $\frac{\sin\, 5x}{\sin x} = \frac{6}{25} - 1 = - \frac{19}{25}$
 
  • #3
kaliprasad said:
$\frac{\sin\, 3x}{\sin\, x}=\frac{6}{5}$ given
subtract 1 from both sides
$\frac{\sin\, 3x - \sin\, x}{\sin\, x}=\frac{1}{5}$
or $\frac{2 \sin\, x \cos\, 2x}{\sin\, x}=\frac{1}{5}$
or $\cos \, 2x = \frac{1}{10}\cdots(1)$
now
$\frac{\sin\, 5x + \sin \,x }{\sin x} = \frac{2 \sin\,3x \cos \,2x }{\sin x}$
$=2 \cos \,2x \frac{\sin\,3x}{\sin x}$
$=2 * \frac{1}{10} * \frac{6}{5} = \frac{6}{25}$
hence $\frac{\sin\, 5x}{\sin x} = \frac{6}{25} - 1 = - \frac{19}{25}$

Good job kaliprasad!(Cool)
 

Related to What is the ratio of sin 5x to sin x in this Trigonometric Challenge?

1. What is the Trigonometric Challenge?

The Trigonometric Challenge is a mathematical problem-solving game that involves using trigonometric functions such as sine, cosine, and tangent to solve various puzzles and challenges.

2. Who can play the Trigonometric Challenge?

Anyone with a basic understanding of trigonometric functions can play the Trigonometric Challenge. It is suitable for students, teachers, and anyone interested in learning or practicing their trigonometry skills.

3. How do I play the Trigonometric Challenge?

To play the Trigonometric Challenge, you need to solve a series of puzzles and challenges by using trigonometric functions. These challenges can be solved using a pencil and paper or a scientific calculator.

4. What are the benefits of playing the Trigonometric Challenge?

Playing the Trigonometric Challenge can help improve your problem-solving skills, strengthen your understanding of trigonometric functions, and enhance your mathematical reasoning abilities.

5. Where can I find the Trigonometric Challenge?

You can find the Trigonometric Challenge online on various websites, or you can purchase a physical copy of the game from educational stores or online retailers.

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