Fatima Wants To Find The Value Of Sin ⁡ Θ \sin \theta Sin Θ , Given Cot ⁡ Θ = 4 7 \cot \theta=\frac{4}{7} Cot Θ = 7 4 ​ . Which Identity Would Be Best For Fatima To Use?A. Cos ⁡ Θ = 1 Sec ⁡ Θ \cos \theta=\frac{1}{\sec \theta} Cos Θ = S E C Θ 1 ​ B. Sin ⁡ 2 Θ + Cos ⁡ 2 Θ = 1 \sin^2 \theta+\cos^2 \theta=1 Sin 2 Θ + Cos 2 Θ = 1 C. $\csc

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Finding the Value of sinθ\sin \theta Using Trigonometric Identities

In trigonometry, there are various identities that can be used to find the values of different trigonometric functions. When given the value of one trigonometric function, we can use these identities to find the values of other trigonometric functions. In this article, we will discuss how to find the value of sinθ\sin \theta using the given value of cotθ\cot \theta.

Understanding the Given Information

Fatima is given the value of cotθ\cot \theta as 47\frac{4}{7}. We know that cotθ=cosθsinθ\cot \theta = \frac{\cos \theta}{\sin \theta}. Therefore, we can write cosθsinθ=47\frac{\cos \theta}{\sin \theta} = \frac{4}{7}.

Choosing the Right Identity

Now, we need to choose the right identity to find the value of sinθ\sin \theta. Let's analyze the given options:

A. cosθ=1secθ\cos \theta = \frac{1}{\sec \theta}

This identity is not helpful in this case because we are given the value of cotθ\cot \theta, not secθ\sec \theta.

B. sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1

This identity is also not helpful because we are given the value of cotθ\cot \theta, not sinθ\sin \theta or cosθ\cos \theta.

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

This identity is not directly helpful because we are given the value of cotθ\cot \theta, not cscθ\csc \theta.

However, we can use the identity cotθ=cosθsinθ\cot \theta = \frac{\cos \theta}{\sin \theta} to find the value of cosθ\cos \theta in terms of sinθ\sin \theta. We can then use the identity sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1 to find the value of sinθ\sin \theta.

Using the Pythagorean Identity

Let's use the Pythagorean identity sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1 to find the value of sinθ\sin \theta. We can rewrite this identity as cos2θ=1sin2θ\cos^2 \theta = 1 - \sin^2 \theta.

We are given the value of cotθ\cot \theta as 47\frac{4}{7}. We can use this value to find the value of cosθ\cos \theta in terms of sinθ\sin \theta. Let's assume cosθ=ksinθ\cos \theta = k \sin \theta, where kk is a constant.

Substituting this value into the Pythagorean identity, we get:

k2sin2θ=1sin2θk^2 \sin^2 \theta = 1 - \sin^2 \theta

Simplifying this equation, we get:

k2sin2θ+sin2θ=1k^2 \sin^2 \theta + \sin^2 \theta = 1

Combining like terms, we get:

(k2+1)sin2θ=1(k^2 + 1) \sin^2 \theta = 1

Now, we can substitute the value of cotθ\cot \theta as 47\frac{4}{7} into this equation. We get:

(47)2+1=k2+1(\frac{4}{7})^2 + 1 = k^2 + 1

Simplifying this equation, we get:

k2=1649k^2 = \frac{16}{49}

Taking the square root of both sides, we get:

k=±47k = \pm \frac{4}{7}

Since cosθ=ksinθ\cos \theta = k \sin \theta, we can write:

cosθ=±47sinθ\cos \theta = \pm \frac{4}{7} \sin \theta

Now, we can use the Pythagorean identity to find the value of sinθ\sin \theta. We get:

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

Substituting the value of cosθ\cos \theta, we get:

sin2θ+(±47sinθ)2=1\sin^2 \theta + (\pm \frac{4}{7} \sin \theta)^2 = 1

Simplifying this equation, we get:

sin2θ+1649sin2θ=1\sin^2 \theta + \frac{16}{49} \sin^2 \theta = 1

Combining like terms, we get:

(6549)sin2θ=1(\frac{65}{49}) \sin^2 \theta = 1

Now, we can solve for sinθ\sin \theta. We get:

sin2θ=4965\sin^2 \theta = \frac{49}{65}

Taking the square root of both sides, we get:

sinθ=±4965\sin \theta = \pm \sqrt{\frac{49}{65}}

Simplifying this expression, we get:

sinθ=±765\sin \theta = \pm \frac{7}{\sqrt{65}}

Therefore, the value of sinθ\sin \theta is ±765\pm \frac{7}{\sqrt{65}}.

In this article, we discussed how to find the value of sinθ\sin \theta using the given value of cotθ\cot \theta. We used the Pythagorean identity to find the value of sinθ\sin \theta. We also analyzed the given options and chose the right identity to find the value of sinθ\sin \theta. The final answer is ±765\pm \frac{7}{\sqrt{65}}.
Q&A: Finding the Value of sinθ\sin \theta Using Trigonometric Identities

In our previous article, we discussed how to find the value of sinθ\sin \theta using the given value of cotθ\cot \theta. We used the Pythagorean identity to find the value of sinθ\sin \theta. In this article, we will answer some frequently asked questions related to finding the value of sinθ\sin \theta using trigonometric identities.

Q: What is the Pythagorean identity?

A: The Pythagorean identity is a fundamental identity in trigonometry that states sin2θ+cos2θ=1\sin^2 \theta + \cos^2 \theta = 1. This identity can be used to find the value of sinθ\sin \theta or cosθ\cos \theta if one of them is known.

Q: How can I use the Pythagorean identity to find the value of sinθ\sin \theta?

A: To use the Pythagorean identity to find the value of sinθ\sin \theta, you need to know the value of cosθ\cos \theta. You can then substitute the value of cosθ\cos \theta into the Pythagorean identity and solve for sinθ\sin \theta.

Q: What if I don't know the value of cosθ\cos \theta? Can I still use the Pythagorean identity?

A: Yes, you can still use the Pythagorean identity even if you don't know the value of cosθ\cos \theta. You can use the identity cotθ=cosθsinθ\cot \theta = \frac{\cos \theta}{\sin \theta} to find the value of cosθ\cos \theta in terms of sinθ\sin \theta. You can then substitute this value into the Pythagorean identity and solve for sinθ\sin \theta.

Q: How can I find the value of cosθ\cos \theta in terms of sinθ\sin \theta?

A: To find the value of cosθ\cos \theta in terms of sinθ\sin \theta, you can use the identity cotθ=cosθsinθ\cot \theta = \frac{\cos \theta}{\sin \theta}. You can then rewrite this identity as cosθ=cotθsinθ\cos \theta = \cot \theta \sin \theta. This gives you the value of cosθ\cos \theta in terms of sinθ\sin \theta.

Q: What if I get a negative value for sinθ\sin \theta? Is that possible?

A: Yes, it is possible to get a negative value for sinθ\sin \theta. The value of sinθ\sin \theta can be positive or negative, depending on the quadrant in which the angle θ\theta lies.

Q: How can I determine the quadrant in which the angle θ\theta lies?

A: To determine the quadrant in which the angle θ\theta lies, you can use the following rules:

  • If sinθ>0\sin \theta > 0, then θ\theta lies in the first or second quadrant.
  • If sinθ<0\sin \theta < 0, then θ\theta lies in the third or fourth quadrant.

Q: What if I get a complex value for sinθ\sin \theta? Is that possible?

A: No, it is not possible to get a complex value for sinθ\sin \theta. The value of sinθ\sin \theta is always a real number.

In this article, we answered some frequently asked questions related to finding the value of sinθ\sin \theta using trigonometric identities. We discussed how to use the Pythagorean identity to find the value of sinθ\sin \theta, how to find the value of cosθ\cos \theta in terms of sinθ\sin \theta, and how to determine the quadrant in which the angle θ\theta lies. We also discussed the possibility of getting a negative or complex value for sinθ\sin \theta.