Rewrite The Following Equation And Options In A Clearer Format:7) Y = -2 + \csc \left(\theta + \frac{\pi}{4}\right ]a. B.

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Introduction

Trigonometric equations can be complex and challenging to understand, especially when they involve multiple trigonometric functions and angles. In this article, we will focus on rewriting the given equation in a clearer format, making it easier to comprehend and solve. We will also provide options for rewriting the equation, highlighting the importance of clear and concise notation in mathematics.

The Original Equation

The original equation is:

y=2+csc(θ+π4)y = -2 + \csc \left(\theta + \frac{\pi}{4}\right)

This equation involves the cosecant function, which is the reciprocal of the sine function. The equation also includes an angle addition, where the angle θ\theta is added to π4\frac{\pi}{4}.

Rewriting the Equation

To rewrite the equation in a clearer format, we can start by using the reciprocal identity of the cosecant function:

cscθ=1sinθ\csc \theta = \frac{1}{\sin \theta}

Substituting this identity into the original equation, we get:

y=2+1sin(θ+π4)y = -2 + \frac{1}{\sin \left(\theta + \frac{\pi}{4}\right)}

This rewritten equation is more straightforward and easier to understand, as it eliminates the need to remember the reciprocal identity of the cosecant function.

Option 1: Using the Angle Addition Formula

Another way to rewrite the equation is by using the angle addition formula for sine:

sin(A+B)=sinAcosB+cosAsinB\sin (A + B) = \sin A \cos B + \cos A \sin B

Applying this formula to the rewritten equation, we get:

y=2+1sinθcosπ4+cosθsinπ4y = -2 + \frac{1}{\sin \theta \cos \frac{\pi}{4} + \cos \theta \sin \frac{\pi}{4}}

This option provides a more detailed and explicit expression for the sine function, making it easier to work with.

Option 2: Using the Half-Angle Formula

The half-angle formula for sine is:

sinθ2=±1cosθ2\sin \frac{\theta}{2} = \pm \sqrt{\frac{1 - \cos \theta}{2}}

We can use this formula to rewrite the equation as:

y=2+1sin(θ2+π8)y = -2 + \frac{1}{\sin \left(\frac{\theta}{2} + \frac{\pi}{8}\right)}

This option provides a different perspective on the equation, highlighting the relationship between the angle θ\theta and the half-angle θ2\frac{\theta}{2}.

Conclusion

Rewriting trigonometric equations in a clearer format is essential for understanding and solving them. By using identities, formulas, and notation, we can make complex equations more manageable and easier to work with. In this article, we have provided three options for rewriting the given equation, each with its own advantages and perspectives. By choosing the most suitable option, we can gain a deeper understanding of the equation and its underlying mathematics.

Further Reading

For more information on trigonometric equations and identities, we recommend the following resources:

Q: What is the difference between the sine and cosecant functions?

A: The sine function, denoted by sinθ\sin \theta, is the ratio of the length of the opposite side to the length of the hypotenuse in a right triangle. The cosecant function, denoted by cscθ\csc \theta, is the reciprocal of the sine function, or 1sinθ\frac{1}{\sin \theta}.

Q: How do I rewrite a trigonometric equation in a clearer format?

A: To rewrite a trigonometric equation in a clearer format, you can use identities, formulas, and notation to simplify the equation. Some common techniques include:

  • Using reciprocal identities to eliminate fractions
  • Applying angle addition and subtraction formulas to simplify expressions
  • Using half-angle formulas to express sine and cosine functions in terms of the half-angle

Q: What is the angle addition formula for sine?

A: The angle addition formula for sine is:

sin(A+B)=sinAcosB+cosAsinB\sin (A + B) = \sin A \cos B + \cos A \sin B

This formula allows you to express the sine of a sum of two angles in terms of the sines and cosines of the individual angles.

Q: How do I use the half-angle formula for sine?

A: The half-angle formula for sine is:

sinθ2=±1cosθ2\sin \frac{\theta}{2} = \pm \sqrt{\frac{1 - \cos \theta}{2}}

To use this formula, you can substitute the half-angle θ2\frac{\theta}{2} into the equation and simplify. Be careful to consider the sign of the square root, as it may be positive or negative depending on the value of θ\theta.

Q: What are some common trigonometric identities?

A: Some common trigonometric identities include:

  • Reciprocal identities: cscθ=1sinθ\csc \theta = \frac{1}{\sin \theta}, secθ=1cosθ\sec \theta = \frac{1}{\cos \theta}
  • Pythagorean identities: sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1, tan2θ+1=sec2θ\tan^2 \theta + 1 = \sec^2 \theta
  • Angle addition and subtraction formulas: sin(A+B)=sinAcosB+cosAsinB\sin (A + B) = \sin A \cos B + \cos A \sin B, cos(A+B)=cosAcosBsinAsinB\cos (A + B) = \cos A \cos B - \sin A \sin B
  • Half-angle formulas: sinθ2=±1cosθ2\sin \frac{\theta}{2} = \pm \sqrt{\frac{1 - \cos \theta}{2}}, cosθ2=±1+cosθ2\cos \frac{\theta}{2} = \pm \sqrt{\frac{1 + \cos \theta}{2}}

Q: How do I apply trigonometric identities to solve equations?

A: To apply trigonometric identities to solve equations, you can use the following steps:

  1. Identify the trigonometric function(s) involved in the equation
  2. Choose the appropriate identity to simplify the equation
  3. Substitute the identity into the equation and simplify
  4. Solve the resulting equation for the unknown variable

Q: What are some common mistakes to avoid when working with trigonometric equations?

A: Some common mistakes to avoid when working with trigonometric equations include:

  • Failing to consider the domain and range of the trigonometric function(s) involved
  • Not using the correct identity or formula
  • Not simplifying the equation correctly
  • Not checking the solution(s) for validity

By avoiding these common mistakes and using the techniques and formulas outlined in this article, you can develop a deeper understanding of trigonometric equations and improve your problem-solving skills.