A Student Uses The Equation Tan ⁡ Θ = S 2 49 \tan \theta = \frac{s^2}{49} Tan Θ = 49 S 2 ​ To Represent The Speed, S S S , In Feet Per Second, Of A Toy Car Driving Around A Circular Track Having An Angle Of Incline Θ \theta Θ , Where $\sin \theta =

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Introduction

In mathematics, trigonometric equations are used to represent various real-world problems, such as the motion of objects in physics. A student is given the equation tanθ=s249\tan \theta = \frac{s^2}{49}, where sinθ=35\sin \theta = \frac{3}{5}, to find the speed, ss, in feet per second, of a toy car driving around a circular track having an angle of incline θ\theta. In this article, we will guide the student through the process of solving this trigonometric equation and provide a step-by-step solution.

Understanding the Given Equation

The given equation is tanθ=s249\tan \theta = \frac{s^2}{49}, where sinθ=35\sin \theta = \frac{3}{5}. To solve for ss, we need to first find the value of tanθ\tan \theta. Since we are given the value of sinθ\sin \theta, we can use the Pythagorean identity to find the value of cosθ\cos \theta.

Using the Pythagorean Identity

The Pythagorean identity states that sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1. We can rearrange this equation to solve for cosθ\cos \theta:

cos2θ=1sin2θ\cos^2 \theta = 1 - \sin^2 \theta

Substituting the given value of sinθ=35\sin \theta = \frac{3}{5}, we get:

cos2θ=1(35)2\cos^2 \theta = 1 - \left(\frac{3}{5}\right)^2

Simplifying the equation, we get:

cos2θ=1925\cos^2 \theta = 1 - \frac{9}{25}

cos2θ=1625\cos^2 \theta = \frac{16}{25}

Taking the square root of both sides, we get:

cosθ=±1625\cos \theta = \pm \sqrt{\frac{16}{25}}

Since the angle of incline θ\theta is positive, we take the positive square root:

cosθ=45\cos \theta = \frac{4}{5}

Finding the Value of tanθ\tan \theta

Now that we have the values of sinθ\sin \theta and cosθ\cos \theta, we can find the value of tanθ\tan \theta using the definition of the tangent function:

tanθ=sinθcosθ\tan \theta = \frac{\sin \theta}{\cos \theta}

Substituting the values of sinθ=35\sin \theta = \frac{3}{5} and cosθ=45\cos \theta = \frac{4}{5}, we get:

tanθ=3545\tan \theta = \frac{\frac{3}{5}}{\frac{4}{5}}

Simplifying the equation, we get:

tanθ=34\tan \theta = \frac{3}{4}

Substituting the Value of tanθ\tan \theta into the Given Equation

Now that we have the value of tanθ\tan \theta, we can substitute it into the given equation:

tanθ=s249\tan \theta = \frac{s^2}{49}

Substituting the value of tanθ=34\tan \theta = \frac{3}{4}, we get:

34=s249\frac{3}{4} = \frac{s^2}{49}

Solving for ss

To solve for ss, we can cross-multiply the equation:

349=4s23 \cdot 49 = 4 \cdot s^2

Simplifying the equation, we get:

147=4s2147 = 4 \cdot s^2

Dividing both sides by 4, we get:

1474=s2\frac{147}{4} = s^2

Taking the square root of both sides, we get:

s=±1474s = \pm \sqrt{\frac{147}{4}}

Since the speed ss is positive, we take the positive square root:

s=1472s = \frac{\sqrt{147}}{2}

Conclusion

In this article, we guided a student through the process of solving a trigonometric equation involving speed and angle of incline. We used the Pythagorean identity to find the value of cosθ\cos \theta, and then used the definition of the tangent function to find the value of tanθ\tan \theta. We then substituted the value of tanθ\tan \theta into the given equation and solved for ss. The final answer is 1472\boxed{\frac{\sqrt{147}}{2}}.

Final Answer

The final answer is 1472\boxed{\frac{\sqrt{147}}{2}}.

Introduction

In our previous article, we guided a student through the process of solving a trigonometric equation involving speed and angle of incline. We used the Pythagorean identity to find the value of cosθ\cos \theta, and then used the definition of the tangent function to find the value of tanθ\tan \theta. We then substituted the value of tanθ\tan \theta into the given equation and solved for ss. In this article, we will provide a Q&A section to help students better understand the solution and address any questions they may have.

Q&A

Q: What is the Pythagorean identity, and how is it used in this problem?

A: The Pythagorean identity is a fundamental concept in trigonometry that states sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1. We use this identity to find the value of cosθ\cos \theta when we are given the value of sinθ\sin \theta. In this problem, we are given sinθ=35\sin \theta = \frac{3}{5}, so we can use the Pythagorean identity to find cosθ=45\cos \theta = \frac{4}{5}.

Q: Why do we take the positive square root of cos2θ\cos^2 \theta?

A: We take the positive square root of cos2θ\cos^2 \theta because the angle of incline θ\theta is positive. If we were dealing with a negative angle, we would take the negative square root.

Q: How do we find the value of tanθ\tan \theta?

A: We find the value of tanθ\tan \theta using the definition of the tangent function: tanθ=sinθcosθ\tan \theta = \frac{\sin \theta}{\cos \theta}. In this problem, we are given sinθ=35\sin \theta = \frac{3}{5} and cosθ=45\cos \theta = \frac{4}{5}, so we can substitute these values into the definition of the tangent function to find tanθ=34\tan \theta = \frac{3}{4}.

Q: Why do we cross-multiply the equation 34=s249\frac{3}{4} = \frac{s^2}{49}?

A: We cross-multiply the equation 34=s249\frac{3}{4} = \frac{s^2}{49} to solve for ss. By cross-multiplying, we can eliminate the fractions and solve for ss.

Q: What is the final answer, and how do we interpret it?

A: The final answer is 1472\boxed{\frac{\sqrt{147}}{2}}. This means that the speed ss of the toy car is 1472\frac{\sqrt{147}}{2} feet per second.

Common Mistakes to Avoid

1. Not using the Pythagorean identity to find the value of cosθ\cos \theta

Make sure to use the Pythagorean identity to find the value of cosθ\cos \theta when you are given the value of sinθ\sin \theta.

2. Not taking the positive square root of cos2θ\cos^2 \theta

Make sure to take the positive square root of cos2θ\cos^2 \theta when the angle of incline θ\theta is positive.

3. Not using the definition of the tangent function to find the value of tanθ\tan \theta

Make sure to use the definition of the tangent function to find the value of tanθ\tan \theta when you are given the values of sinθ\sin \theta and cosθ\cos \theta.

Conclusion

In this Q&A article, we addressed common questions and misconceptions about solving a trigonometric equation involving speed and angle of incline. We hope that this article has helped students better understand the solution and address any questions they may have. Remember to use the Pythagorean identity to find the value of cosθ\cos \theta, take the positive square root of cos2θ\cos^2 \theta, and use the definition of the tangent function to find the value of tanθ\tan \theta.