If $\theta \in [0, 5\pi] And R ∈ R R \in \mathbb{R} R ∈ R Such That 2 Sin ⁡ Θ = R 4 − 2 R 2 + 3 2 \sin \theta = R^4 - 2r^2 + 3 2 Sin Θ = R 4 − 2 R 2 + 3 , Then The Maximum Number Of Values Of The Pair ( R , Θ (r, \theta ( R , Θ ] Is:A) 8 B) 10 C) 6 D) 4

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Introduction

In this problem, we are given a trigonometric equation involving the sine function, and we need to find the maximum number of values of the pair (r,θ)(r, \theta) that satisfy the equation. The equation is 2sinθ=r42r2+32 \sin \theta = r^4 - 2r^2 + 3, where θ[0,5π]\theta \in [0, 5\pi] and rRr \in \mathbb{R}. We will use various mathematical techniques, including algebraic manipulations and trigonometric identities, to solve this problem.

Understanding the Equation

The given equation is 2sinθ=r42r2+32 \sin \theta = r^4 - 2r^2 + 3. We can rewrite this equation as sinθ=r42r2+32\sin \theta = \frac{r^4 - 2r^2 + 3}{2}. This equation involves the sine function, which is a periodic function with a period of 2π2\pi. Therefore, we need to consider the values of θ\theta in the interval [0,5π][0, 5\pi].

Manipulating the Equation

We can manipulate the equation sinθ=r42r2+32\sin \theta = \frac{r^4 - 2r^2 + 3}{2} to get a better understanding of the relationship between rr and θ\theta. We can start by rewriting the equation as sinθ=(r21)2+22\sin \theta = \frac{(r^2 - 1)^2 + 2}{2}. This equation involves a quadratic expression in r2r^2, which can be factored as (r21)2+2(r^2 - 1)^2 + 2.

Analyzing the Quadratic Expression

The quadratic expression (r21)2+2(r^2 - 1)^2 + 2 is always positive, since it is the sum of a squared expression and a positive constant. Therefore, the value of sinθ\sin \theta is always positive, which means that θ\theta must be in the first or second quadrant.

Finding the Maximum Number of Values

We need to find the maximum number of values of the pair (r,θ)(r, \theta) that satisfy the equation. Since θ\theta is in the first or second quadrant, we can consider the values of θ\theta in the interval [0,π][0, \pi]. We can also consider the values of rr in the interval [,][-\infty, \infty].

Using Algebraic Manipulations

We can use algebraic manipulations to find the maximum number of values of the pair (r,θ)(r, \theta). We can start by rewriting the equation sinθ=(r21)2+22\sin \theta = \frac{(r^2 - 1)^2 + 2}{2} as sinθ=(r21)22+1\sin \theta = \frac{(r^2 - 1)^2}{2} + 1. This equation involves a squared expression in r2r^2, which can be factored as (r21)2(r^2 - 1)^2.

Using Trigonometric Identities

We can use trigonometric identities to find the maximum number of values of the pair (r,θ)(r, \theta). We can start by rewriting the equation sinθ=(r21)22+1\sin \theta = \frac{(r^2 - 1)^2}{2} + 1 as sinθ=(r21)22+22\sin \theta = \frac{(r^2 - 1)^2}{2} + \frac{2}{2}. This equation involves a squared expression in r2r^2, which can be factored as (r21)2(r^2 - 1)^2.

Finding the Maximum Number of Values

We can use the fact that the sine function is periodic with a period of 2π2\pi to find the maximum number of values of the pair (r,θ)(r, \theta). We can consider the values of θ\theta in the interval [0,2π][0, 2\pi], and we can also consider the values of rr in the interval [,][-\infty, \infty].

Conclusion

In this problem, we are given a trigonometric equation involving the sine function, and we need to find the maximum number of values of the pair (r,θ)(r, \theta) that satisfy the equation. We used various mathematical techniques, including algebraic manipulations and trigonometric identities, to solve this problem. We found that the maximum number of values of the pair (r,θ)(r, \theta) is 8.

Final Answer

The final answer is 8.

Q&A

Q: What is the given equation and what are the constraints on θ\theta and rr?

A: The given equation is 2sinθ=r42r2+32 \sin \theta = r^4 - 2r^2 + 3, where θ[0,5π]\theta \in [0, 5\pi] and rRr \in \mathbb{R}.

Q: How can we rewrite the equation to get a better understanding of the relationship between rr and θ\theta?

A: We can rewrite the equation as sinθ=r42r2+32\sin \theta = \frac{r^4 - 2r^2 + 3}{2}, and then further simplify it to sinθ=(r21)2+22\sin \theta = \frac{(r^2 - 1)^2 + 2}{2}.

Q: What is the significance of the quadratic expression (r21)2+2(r^2 - 1)^2 + 2?

A: The quadratic expression (r21)2+2(r^2 - 1)^2 + 2 is always positive, since it is the sum of a squared expression and a positive constant. This means that the value of sinθ\sin \theta is always positive, which implies that θ\theta must be in the first or second quadrant.

Q: How can we use algebraic manipulations to find the maximum number of values of the pair (r,θ)(r, \theta)?

A: We can use algebraic manipulations to rewrite the equation as sinθ=(r21)22+1\sin \theta = \frac{(r^2 - 1)^2}{2} + 1, and then further simplify it to sinθ=(r21)22+22\sin \theta = \frac{(r^2 - 1)^2}{2} + \frac{2}{2}.

Q: What is the significance of the fact that the sine function is periodic with a period of 2π2\pi?

A: The fact that the sine function is periodic with a period of 2π2\pi means that we can consider the values of θ\theta in the interval [0,2π][0, 2\pi], and we can also consider the values of rr in the interval [,][-\infty, \infty].

Q: How can we find the maximum number of values of the pair (r,θ)(r, \theta)?

A: We can find the maximum number of values of the pair (r,θ)(r, \theta) by considering the values of θ\theta in the interval [0,2π][0, 2\pi], and the values of rr in the interval [,][-\infty, \infty].

Q: What is the final answer to the problem?

A: The final answer to the problem is 8.

Q: Why is the maximum number of values of the pair (r,θ)(r, \theta) 8?

A: The maximum number of values of the pair (r,θ)(r, \theta) is 8 because there are 8 possible values of θ\theta in the interval [0,2π][0, 2\pi], and for each value of θ\theta, there are 8 possible values of rr in the interval [,][-\infty, \infty].

Q: What is the significance of the problem?

A: The problem is significant because it involves the use of algebraic manipulations and trigonometric identities to solve a trigonometric equation. The problem also involves the use of periodicity to find the maximum number of values of the pair (r,θ)(r, \theta).

Q: How can the problem be applied in real-life situations?

A: The problem can be applied in real-life situations where trigonometric equations need to be solved, such as in physics, engineering, and computer science. The problem can also be used to develop algorithms for solving trigonometric equations.