# Same Derivatives Implies Same Functions? | Summary and Q&A

37.7K views
July 19, 2018
by
blackpenredpen
Same Derivatives Implies Same Functions?

## TL;DR

This video explains how to simplify a trigonometric expression using calculus, ultimately demonstrating that two trig expressions are equal.

## Key Insights

• 😑 The video demonstrates the use of calculus techniques, specifically the chain rule, to simplify trigonometric expressions.
• 😑 Algebraic manipulations are used extensively to simplify the expression step by step.
• 😑 The video shows that the simplified expression is equivalent to a known trig identity through substitution of values.
• 😑 The importance of recognizing when two expressions differ by a constant value is highlighted.
• 🎮 The video emphasizes the importance of reviewing derivatives and fundamental calculus concepts.
• 😑 The use of inverse trigonometric functions to simplify trig expressions is showcased.
• 😑 The video demonstrates the power of algebraic techniques in simplifying complex mathematical expressions.

## Transcript

okay this video show you guys how to differentiate this function right here and in the end you'll see that is actually a nice simplification and also another question I wanted to ask but first of all I would like to know I can't focus that the rough job in first tangent X hmm it's 1 over 1 plus x squared but since this right here we have this thing... Read More

### Q: What is the initial trig expression being simplified in the video?

The initial trig expression being simplified is the inverse tangent of X minus the square root of x squared plus 1.

### Q: How is the chain rule used in the simplification process?

The chain rule is applied to find the derivative of the inner function in the expression, which involves multiplying by the derivative of the inside function.

### Q: How are algebraic manipulations used to simplify the expression?

Algebraic manipulations such as expanding squares and combining like terms are used to simplify the expression and rewrite it in a simpler form.

### Q: How does the video demonstrate that the simplified expression is equal to a known trig identity?

By picking a value for X and plugging it into both the simplified expression and the known trig identity, the video shows that they produce the same result, proving their equality.

## Summary & Key Takeaways

• The video demonstrates the step-by-step process of simplifying a trig expression using calculus.

• The chain rule and algebraic manipulations are applied to simplify the expression.

• The simplified expression is then compared to a known trig identity, showing that they are equal.