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ARCTANGENT

Arctangent

Definition Of Arctangent

Arctangent is the inverse function of tangent. It is also written as arctan or tan-1. If y = tan x, then x = arctan y.

Examples of Arctangent

tan-1 1 = 450 or arctangent (1) = 450. This means that the angle 450 has tangent equal to 1.

Video Examples: Arctan Inverse Trig Function

Solved Example on Arctangent

Ques: Find the value of sec [arctan img].

Choices:

A. img
B. img
C. img
D. img
Correct Answer: B

Solution:

Step 1: Let B = arctan img. Then tan B = .img
Step 2: So, sec [arctan img] = sec [arctan(tan B)].
Step 3: = sec B 
Step 4: From the figure, we observe that sec B = img . 
example of ArctangentStep 5: So, sec[arctan img] = img.

Quick Summary

  • Arctangent is the inverse of the tangent function.
  • It's denoted as arctan(x) or tan⁻¹(x).
  • It gives the angle whose tangent is x.
  • The range of arctangent is (-π/2, π/2) radians or (-90°, 90°).
\[ x = \arctan(y) \Leftrightarrow y = \tan(x) \]

🍎 Teacher Insights

Emphasize the difference between arctangent and the reciprocal of tangent. Use the unit circle to visually represent the relationship between tangent and arctangent. Provide real-world examples where arctangent is used, such as finding the angle of elevation.

🎓 Prerequisites

  • Tangent function
  • Inverse functions
  • Unit circle
  • Pythagorean theorem

Check Your Knowledge

Q1: What is arctan(1)?

Q2: The range of arctangent function is?

Frequently Asked Questions

Q: What is the domain of the arctangent function?
A: The domain of the arctangent function is all real numbers.

Q: What is the range of the arctangent function?
A: The range of the arctangent function is (-π/2, π/2) radians or (-90°, 90°).

Q: How do I find the arctangent of a number?
A: Use a calculator or trigonometric tables to find the angle whose tangent is the given number.

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