Evaluate The Expression: ${ 3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} =\$} A. { -\sqrt{3}$}$B. 0C. { \sqrt{3}$}$D. ${$2 \sqrt{3}$}$85. Which Of The Following Is Correct About An Angle

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Introduction


Trigonometry is a branch of mathematics that deals with the relationships between the sides and angles of triangles. It is a fundamental subject that has numerous applications in various fields, including physics, engineering, and navigation. In this article, we will focus on evaluating trigonometric expressions, specifically the given expression: 3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ}. We will break down the solution step by step and provide a comprehensive explanation of the trigonometric concepts involved.

Understanding the Given Expression


The given expression is a combination of three trigonometric functions: tangent, sine, and cosine. The expression is: 3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ}. To evaluate this expression, we need to understand the properties of each trigonometric function and how they behave with respect to the angle.

Tangent Function


The tangent function is defined as the ratio of the sine and cosine functions: tanโกฮธ=sinโกฮธcosโกฮธ\tan \theta = \frac{\sin \theta}{\cos \theta}. The tangent function has a periodicity of 180โˆ˜180^{\circ}, which means that the value of the tangent function repeats every 180โˆ˜180^{\circ}.

Sine Function


The sine function is defined as the ratio of the opposite side to the hypotenuse in a right-angled triangle. The sine function has a periodicity of 360โˆ˜360^{\circ}, which means that the value of the sine function repeats every 360โˆ˜360^{\circ}.

Cosine Function


The cosine function is defined as the ratio of the adjacent side to the hypotenuse in a right-angled triangle. The cosine function has a periodicity of 360โˆ˜360^{\circ}, which means that the value of the cosine function repeats every 360โˆ˜360^{\circ}.

Evaluating the Expression


To evaluate the given expression, we need to simplify each trigonometric function separately and then combine the results.

Evaluating the Tangent Function


The tangent function is evaluated at 930โˆ˜930^{\circ}. Since the tangent function has a periodicity of 180โˆ˜180^{\circ}, we can rewrite 930โˆ˜930^{\circ} as 930โˆ˜โˆ’6โ‹…180โˆ˜=30โˆ˜930^{\circ} - 6 \cdot 180^{\circ} = 30^{\circ}. Therefore, tanโก930โˆ˜=tanโก30โˆ˜=13\tan 930^{\circ} = \tan 30^{\circ} = \frac{1}{\sqrt{3}}.

Evaluating the Sine Function


The sine function is evaluated at 1200โˆ˜1200^{\circ}. Since the sine function has a periodicity of 360โˆ˜360^{\circ}, we can rewrite 1200โˆ˜1200^{\circ} as 1200โˆ˜โˆ’3โ‹…360โˆ˜=120โˆ˜1200^{\circ} - 3 \cdot 360^{\circ} = 120^{\circ}. Therefore, sinโก1200โˆ˜=sinโก120โˆ˜=32\sin 1200^{\circ} = \sin 120^{\circ} = \frac{\sqrt{3}}{2}.

Evaluating the Cosine Function


The cosine function is evaluated at 1410โˆ˜1410^{\circ}. Since the cosine function has a periodicity of 360โˆ˜360^{\circ}, we can rewrite 1410โˆ˜1410^{\circ} as 1410โˆ˜โˆ’3โ‹…360โˆ˜=150โˆ˜1410^{\circ} - 3 \cdot 360^{\circ} = 150^{\circ}. Therefore, cosโก1410โˆ˜=cosโก150โˆ˜=โˆ’32\cos 1410^{\circ} = \cos 150^{\circ} = -\frac{\sqrt{3}}{2}.

Combining the Results


Now that we have evaluated each trigonometric function separately, we can combine the results to evaluate the given expression.

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=3โ‹…13+32โˆ’(โˆ’32)3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = 3 \cdot \frac{1}{\sqrt{3}} + \frac{\sqrt{3}}{2} - \left(-\frac{\sqrt{3}}{2}\right)

Simplifying the expression, we get:

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=33+32+323 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = \frac{3}{\sqrt{3}} + \frac{\sqrt{3}}{2} + \frac{\sqrt{3}}{2}

Combining the like terms, we get:

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=33+33 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = \frac{3}{\sqrt{3}} + \sqrt{3}

Rationalizing the denominator, we get:

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=333+33 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = \frac{3\sqrt{3}}{3} + \sqrt{3}

Simplifying the expression, we get:

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=3+33 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = \sqrt{3} + \sqrt{3}

Combining the like terms, we get:

3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜=233 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} = 2\sqrt{3}

Therefore, the value of the given expression is 232\sqrt{3}.

Conclusion


In this article, we evaluated the given expression: 3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ}. We broke down the solution step by step and provided a comprehensive explanation of the trigonometric concepts involved. We simplified each trigonometric function separately and then combined the results to evaluate the given expression. The final answer is 232\sqrt{3}.

Frequently Asked Questions


Q: What is the periodicity of the tangent function?

A: The periodicity of the tangent function is 180โˆ˜180^{\circ}.

Q: What is the periodicity of the sine function?

A: The periodicity of the sine function is 360โˆ˜360^{\circ}.

Q: What is the periodicity of the cosine function?

A: The periodicity of the cosine function is 360โˆ˜360^{\circ}.

Q: How do you evaluate the tangent function at a given angle?

A: To evaluate the tangent function at a given angle, you need to rewrite the angle in terms of the periodicity of the tangent function.

Q: How do you evaluate the sine function at a given angle?

A: To evaluate the sine function at a given angle, you need to rewrite the angle in terms of the periodicity of the sine function.

Q: How do you evaluate the cosine function at a given angle?

A: To evaluate the cosine function at a given angle, you need to rewrite the angle in terms of the periodicity of the cosine function.

References


  • [1] "Trigonometry" by Michael Corral
  • [2] "Trigonometry" by I. M. Gelfand
  • [3] "Trigonometry" by Charles P. McKeague

Note: The references provided are for general information purposes only and are not specific to the given expression.

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Q&A: Evaluating Trigonometric Expressions


Q: What is the value of the expression 3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ}?

A: The value of the expression 3tanโก930โˆ˜+sinโก1200โˆ˜โˆ’cosโก1410โˆ˜3 \tan 930^{\circ} + \sin 1200^{\circ} - \cos 1410^{\circ} is 232\sqrt{3}.

Q: How do you evaluate the tangent function at a given angle?

A: To evaluate the tangent function at a given angle, you need to rewrite the angle in terms of the periodicity of the tangent function. The periodicity of the tangent function is 180โˆ˜180^{\circ}.

Q: How do you evaluate the sine function at a given angle?

A: To evaluate the sine function at a given angle, you need to rewrite the angle in terms of the periodicity of the sine function. The periodicity of the sine function is 360โˆ˜360^{\circ}.

Q: How do you evaluate the cosine function at a given angle?

A: To evaluate the cosine function at a given angle, you need to rewrite the angle in terms of the periodicity of the cosine function. The periodicity of the cosine function is 360โˆ˜360^{\circ}.

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

A: The sine and cosine functions are both trigonometric functions that are used to describe the relationships between the sides and angles of triangles. However, the sine function is defined as the ratio of the opposite side to the hypotenuse, while the cosine function is defined as the ratio of the adjacent side to the hypotenuse.

Q: What is the value of the expression tanโก45โˆ˜\tan 45^{\circ}?

A: The value of the expression tanโก45โˆ˜\tan 45^{\circ} is 1.

Q: What is the value of the expression sinโก90โˆ˜\sin 90^{\circ}?

A: The value of the expression sinโก90โˆ˜\sin 90^{\circ} is 1.

Q: What is the value of the expression cosโก0โˆ˜\cos 0^{\circ}?

A: The value of the expression cosโก0โˆ˜\cos 0^{\circ} is 1.

Q: How do you simplify a trigonometric expression?

A: To simplify a trigonometric expression, you need to use the properties of the trigonometric functions, such as the sum and difference formulas, and the Pythagorean identity.

Q: What is the Pythagorean identity?

A: The Pythagorean identity is a fundamental property of the trigonometric functions that states that sinโก2ฮธ+cosโก2ฮธ=1\sin^2 \theta + \cos^2 \theta = 1.

Q: How do you use the Pythagorean identity to simplify a trigonometric expression?

A: To use the Pythagorean identity to simplify a trigonometric expression, you need to rewrite the expression in terms of the sine and cosine functions, and then use the Pythagorean identity to simplify the expression.

Common Trigonometric Identities


Pythagorean Identity

sinโก2ฮธ+cosโก2ฮธ=1\sin^2 \theta + \cos^2 \theta = 1

Sum Formula for Sine

sinโก(A+B)=sinโกAcosโกB+cosโกAsinโกB\sin (A + B) = \sin A \cos B + \cos A \sin B

Sum Formula for Cosine

cosโก(A+B)=cosโกAcosโกBโˆ’sinโกAsinโกB\cos (A + B) = \cos A \cos B - \sin A \sin B

Difference Formula for Sine

sinโก(Aโˆ’B)=sinโกAcosโกBโˆ’cosโกAsinโกB\sin (A - B) = \sin A \cos B - \cos A \sin B

Difference Formula for Cosine

cosโก(Aโˆ’B)=cosโกAcosโกB+sinโกAsinโกB\cos (A - B) = \cos A \cos B + \sin A \sin B

Trigonometric Functions of Common Angles


Trigonometric Functions of 0ยฐ

sinโก0โˆ˜=0\sin 0^{\circ} = 0 cosโก0โˆ˜=1\cos 0^{\circ} = 1 tanโก0โˆ˜=0\tan 0^{\circ} = 0

Trigonometric Functions of 30ยฐ

sinโก30โˆ˜=12\sin 30^{\circ} = \frac{1}{2} cosโก30โˆ˜=32\cos 30^{\circ} = \frac{\sqrt{3}}{2} tanโก30โˆ˜=13\tan 30^{\circ} = \frac{1}{\sqrt{3}}

Trigonometric Functions of 45ยฐ

sinโก45โˆ˜=22\sin 45^{\circ} = \frac{\sqrt{2}}{2} cosโก45โˆ˜=22\cos 45^{\circ} = \frac{\sqrt{2}}{2} tanโก45โˆ˜=1\tan 45^{\circ} = 1

Trigonometric Functions of 60ยฐ

sinโก60โˆ˜=32\sin 60^{\circ} = \frac{\sqrt{3}}{2} cosโก60โˆ˜=12\cos 60^{\circ} = \frac{1}{2} tanโก60โˆ˜=3\tan 60^{\circ} = \sqrt{3}

Trigonometric Functions of 90ยฐ

sinโก90โˆ˜=1\sin 90^{\circ} = 1 cosโก90โˆ˜=0\cos 90^{\circ} = 0 tanโก90โˆ˜=โˆž\tan 90^{\circ} = \infty

Conclusion


In this article, we have provided a comprehensive guide to evaluating trigonometric expressions. We have covered the basics of trigonometry, including the definition of the trigonometric functions, the properties of the trigonometric functions, and the common trigonometric identities. We have also provided a list of common trigonometric functions of common angles. We hope that this article has been helpful in providing a clear understanding of the subject.