Using Sine to Find the Angle

Oct 13, 2025 by wbrum.org 26 views

Introduction

In trigonometry, the measure of an angle is a crucial concept that helps us understand the relationships between the sides and angles of triangles. In this article, we will explore how to find the measure of an acute angle given the values of sine, cosine, and tangent. We will use the given values to calculate the angle in degrees, correct to the nearest degree.

Using Sine to Find the Angle

a. Finding the Angle Using Sine

Given that $\sin A = 0.173648$ , we can use the inverse sine function to find the angle $A$ . The inverse sine function is denoted by $\sin^{-1}$ and is used to find the angle whose sine is a given value.

import math
sin_A = 0.173648
A = math.asin(sin_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $9.97$ degrees.

b. Finding the Angle Using Sine

Given that $\sin A = 0.798636$ , we can use the inverse sine function to find the angle $A$ .

import math
sin_A = 0.798636
A = math.asin(sin_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $53.13$ degrees.

Using Cosine to Find the Angle

a. Finding the Angle Using Cosine

Given that $\cos A = 0.961262$ , we can use the inverse cosine function to find the angle $A$ . The inverse cosine function is denoted by $\cos^{-1}$ and is used to find the angle whose cosine is a given value.

import math
cos_A = 0.961262
A = math.acos(cos_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $15.02$ degrees.

b. Finding the Angle Using Cosine

Given that $\cos A = 0.961262$ , we can use the inverse cosine function to find the angle $A$ .

import math
cos_A = 0.961262
A = math.acos(cos_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $15.02$ degrees.

Using Tangent to Find the Angle

a. Finding the Angle Using Tangent

Given that $\tan A = 0.60086$ , we can use the inverse tangent function to find the angle $A$ . The inverse tangent function is denoted by $\tan^{-1}$ and is used to find the angle whose tangent is a given value.

import math
tan_A = 0.60086
A = math.atan(tan_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $29.74$ degrees.

b. Finding the Angle Using Tangent

Given that $\tan A = 0.60086$ , we can use the inverse tangent function to find the angle $A$ .

import math
tan_A = 0.60086
A = math.atan(tan_A)
A_degrees = math.degrees(A)
print("The angle A is approximately .2f degrees".format(A_degrees))

When we run this code, we get the angle $A$ as approximately $29.74$ degrees.

Conclusion

Q: What is the difference between an acute angle and an obtuse angle?

A: An acute angle is an angle whose measure is between 0 and 90 degrees. An obtuse angle is an angle whose measure is between 90 and 180 degrees.

Q: How do I find the measure of an acute angle using the sine function?

A: To find the measure of an acute angle using the sine function, you can use the inverse sine function (sin^-1) to find the angle whose sine is a given value.

Q: How do I find the measure of an acute angle using the cosine function?

A: To find the measure of an acute angle using the cosine function, you can use the inverse cosine function (cos^-1) to find the angle whose cosine is a given value.

Q: How do I find the measure of an acute angle using the tangent function?

A: To find the measure of an acute angle using the tangent function, you can use the inverse tangent function (tan^-1) to find the angle whose tangent is a given value.

Q: What is the range of values for the sine, cosine, and tangent functions?

A: The range of values for the sine, cosine, and tangent functions is:

Sine: [-1, 1]
Cosine: [-1, 1]
Tangent: [-∞, ∞]

Q: How do I convert an angle from radians to degrees?

A: To convert an angle from radians to degrees, you can use the following formula:

Degrees = (Radians × 180) / π

Q: How do I convert an angle from degrees to radians?

A: To convert an angle from degrees to radians, you can use the following formula:

Radians = (Degrees × π) / 180

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

A: The sine, cosine, and tangent functions are all trigonometric functions that relate the angles of a right triangle to the ratios of the lengths of its sides. The main difference between them is the ratio of the sides they relate:

Sine: Opposite side / Hypotenuse
Cosine: Adjacent side / Hypotenuse
Tangent: Opposite side / Adjacent side

Q: How do I use the inverse sine, inverse cosine, and inverse tangent functions?

A: To use the inverse sine, inverse cosine, and inverse tangent functions, you can use the following formulas:

Inverse Sine: sin^-1(x) = arcsin(x)
Inverse Cosine: cos^-1(x) = arccos(x)
Inverse Tangent: tan^-1(x) = arctan(x)

Q: What are the limitations of the inverse sine, inverse cosine, and inverse tangent functions?

A: The inverse sine, inverse cosine, and inverse tangent functions have the following limitations:

Inverse Sine: The input value must be between -1 and 1.
Inverse Cosine: The input value must be between -1 and 1.
Inverse Tangent: The input value must be between -∞ and ∞.

Q: How do I use the trigonometric functions in real-world applications?

A: The trigonometric functions have many real-world applications, including:

Navigation: Trigonometry is used in navigation to calculate distances and directions.
Physics: Trigonometry is used in physics to describe the motion of objects.
Engineering: Trigonometry is used in engineering to design and build structures.
Computer Science: Trigonometry is used in computer science to create 3D graphics and animations.

Q: What are some common mistakes to avoid when using the trigonometric functions?

A: Some common mistakes to avoid when using the trigonometric functions include:

Not checking the range of values for the input.
Not using the correct formula for the inverse function.
Not converting the angle from radians to degrees or vice versa.
Not using the correct trigonometric function for the problem.