BrightChamps Logo
Login
Creative Math Ideas Image
Live Math Learners Count Icon119 Learners

Last updated on 6 September 2025

Math Whiteboard Illustration

Derivative of 2sinx

Professor Greenline Explaining Math Concepts

We use the derivative of 2sin(x), which is 2cos(x), as a measuring tool for how the function 2sin(x) changes in response to a slight change in x. Derivatives help us calculate profit or loss in real-life situations. We will now talk about the derivative of 2sin(x) in detail.

Derivative of 2sinx for UAE Students
Professor Greenline from BrightChamps

What is the Derivative of 2sinx?

We now understand the derivative of 2sinx.

It is commonly represented as d/dx (2sinx) or (2sinx)', and its value is 2cosx.

The function 2sinx has a clearly defined derivative, indicating it is differentiable within its domain.

The key concepts are mentioned below:

Sine Function: sin(x) is a basic trigonometric function.

Derivative of Sine: The derivative of sin(x) is cos(x).

Constant Multiplication Rule: If a function is multiplied by a constant, its derivative is the constant multiplied by the derivative of the function.

Professor Greenline from BrightChamps

Derivative of 2sinx Formula

The derivative of 2sinx can be denoted as d/dx (2sinx) or (2sinx)'. The formula we use to differentiate 2sinx is: d/dx (2sinx) = 2cosx (or) (2sinx)' = 2cosx The formula applies to all x.

Professor Greenline from BrightChamps

Proofs of the Derivative of 2sinx

We can derive the derivative of 2sinx using proofs.

To show this, we will use the trigonometric identities along with the rules of differentiation.

There are several methods we use to prove this, such as:

By First Principle

Using the Constant Multiple Rule

Using Chain Rule

We will now demonstrate that the differentiation of 2sinx results in 2cosx using the above-mentioned methods:

 

By First Principle

The derivative of 2sinx can be proved using the First Principle, which expresses the derivative as the limit of the difference quotient.

To find the derivative of 2sinx using the first principle, we will consider f(x) = 2sinx.

Its derivative can be expressed as the following limit. f'(x) = limₕ→₀ [f(x + h) - f(x)] / h … (1)

Given that f(x) = 2sinx, we write f(x + h) = 2sin(x + h). Substituting these into equation (1), f'(x) = limₕ→₀ [2sin(x + h) - 2sinx] / h = limₕ→₀ 2[sin(x + h) - sinx] / h = 2 limₕ→₀ [sin(x + h) - sinx] / h

Using the formula for the derivative of sinx, = 2cosx

Hence, proved.

 

Using Constant Multiplication Rule

To prove the differentiation of 2sinx using the constant multiplication rule,

We use the formula: d/dx [c·f(x)] = c·f'(x) Let c = 2 and f(x) = sinx, so we have, d/dx (2sinx) = 2·d/dx (sinx) = 2cosx

 

Using Chain Rule

To prove the differentiation of 2sinx using the chain rule, Consider y = 2sinx = 2·sinx

Using the chain rule, dy/dx = 2 · d/dx (sinx) = 2cosx

Professor Greenline from BrightChamps

Higher-Order Derivatives of 2sinx

When a function is differentiated several times, the derivatives obtained are referred to as higher-order derivatives. Higher-order derivatives can be a little tricky.

To understand them better, think of a car where the speed changes (first derivative) and the rate at which the speed changes (second derivative) also changes.

Higher-order derivatives make it easier to understand functions like 2sin(x).

For the first derivative of a function, we write f′(x), which indicates how the function changes or its slope at a certain point.

The second derivative is derived from the first derivative, which is denoted using f′′(x).

Similarly, the third derivative, f′′′(x), is the result of the second derivative, and this pattern continues.

For the nth Derivative of 2sin(x), we generally use fⁿ(x) for the nth derivative of a function f(x), which tells us the change in the rate of change (continuing for higher-order derivatives).

Professor Greenline from BrightChamps

Special Cases:

When x is 0 or any multiple of π, the derivative 2cos(x) is not zero since cos(0) = 1, so the derivative is 2. The function 2sinx is continuous and differentiable for all x.

Max Pointing Out Common Math Mistakes

Common Mistakes and How to Avoid Them in Derivatives of 2sinx

Students frequently make mistakes when differentiating 2sinx. These mistakes can be resolved by understanding the proper solutions. Here are a few common mistakes and ways to solve them:

Mistake 1

Red Cross Icon Indicating Mistakes to Avoid in This Math Topic

Not simplifying the equation

Green Checkmark Icon Indicating Correct Solutions in This Math Topic

Students may forget to simplify expressions involving constants, leading to incomplete or incorrect results. They often skip steps and directly arrive at the result, especially when solving using the chain rule. Ensure that each step is written in order. Students might think it is awkward, but it is important to avoid errors in the process.

Mistake 2

Red Cross Icon Indicating Mistakes to Avoid in This Math Topic

Forgetting the Constant Multiplication Rule

Green Checkmark Icon Indicating Correct Solutions in This Math Topic

They might not remember that when a constant multiplies a function, the derivative is the constant multiplied by the derivative of the function. Always apply this rule to correctly find the derivative of functions like 2sinx.

Mistake 3

Red Cross Icon Indicating Mistakes to Avoid in This Math Topic

Incorrect use of Trigonometric Identity

Green Checkmark Icon Indicating Correct Solutions in This Math Topic

While differentiating, students may incorrectly apply trigonometric identities.

 

For example: Incorrect differentiation: d/dx (2sinx) = 2sinx.

The correct differentiation is: d/dx (2sinx) = 2cosx. To avoid this mistake, ensure the correct trigonometric identity and differentiation rules are applied.

Mistake 4

Red Cross Icon Indicating Mistakes to Avoid in This Math Topic

Not writing Constants and Coefficients

Green Checkmark Icon Indicating Correct Solutions in This Math Topic

There is a common mistake where students sometimes forget to multiply the constants placed before sinx.

 

For example, they incorrectly write d/dx (2sinx) = cosx.

Students should check the constants in the terms and ensure they are multiplied properly.

 

For example, the correct equation is d/dx (2sinx) = 2cosx.

Mistake 5

Red Cross Icon Indicating Mistakes to Avoid in This Math Topic

Not Applying the Chain Rule

Green Checkmark Icon Indicating Correct Solutions in This Math Topic

Students often forget to use the chain rule when necessary. This happens when the derivative of the inner function is not considered.

 

For example: Incorrect: d/dx (sin(2x)) = cos(2x).

To fix this error, students should divide the functions into inner and outer parts. Then, make sure that each function is differentiated. For example, d/dx (sin(2x)) = 2cos(2x).

arrow-right
Max from BrightChamps Saying "Hey"
Hey!

Examples Using the Derivative of 2sinx

Ray, the Character from BrightChamps Explaining Math Concepts
Max, the Girl Character from BrightChamps

Problem 1

Calculate the derivative of (2sinx·cosx)

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"
Okay, lets begin

Here, we have f(x) = 2sinx·cosx.

Using the product rule, f'(x) = u′v + uv′ In the given equation, u = 2sinx and v = cosx.

Let’s differentiate each term, u′ = d/dx (2sinx) = 2cosx v′ = d/dx (cosx) = -sinx

Substituting into the given equation, f'(x) = (2cosx)·(cosx) + (2sinx)·(-sinx)

Let’s simplify terms to get the final answer, f'(x) = 2cos²x - 2sin²x

Thus, the derivative of the specified function is 2cos²x - 2sin²x.

Explanation

We find the derivative of the given function by dividing the function into two parts. The first step is finding its derivative and then combining them using the product rule to get the final result.

Max from BrightChamps Praising Clear Math Explanations
Well explained 👍
Max, the Girl Character from BrightChamps

Problem 2

A pendulum swings with its position given by the function y = 2sin(x), where y represents the displacement from the center. If x = π/6 radians, find the velocity of the pendulum.

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"
Okay, lets begin

We have y = 2sin(x) (position of the pendulum)...(1)

Now, we will differentiate the equation (1)

Take the derivative 2sin(x): dy/dx = 2cos(x)

Given x = π/6 (substitute this into the derivative) dy/dx = 2cos(π/6)

We know that cos(π/6) = √3/2 dy/dx = 2(√3/2) = √3

Hence, we get the velocity of the pendulum at x = π/6 as √3.

Explanation

We find the velocity of the pendulum at x = π/6 as √3, which means that at that point, the pendulum is moving at a rate of √3 units per unit time.

Max from BrightChamps Praising Clear Math Explanations
Well explained 👍
Max, the Girl Character from BrightChamps

Problem 3

Derive the second derivative of the function y = 2sin(x).

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"
Okay, lets begin

The first step is to find the first derivative, dy/dx = 2cos(x)...(1)

Now we will differentiate equation (1) to get the second derivative: d²y/dx² = d/dx [2cos(x)]

Here we use the derivative of cos(x), which is -sin(x), d²y/dx² = 2(-sin(x)) = -2sin(x)

Therefore, the second derivative of the function y = 2sin(x) is -2sin(x).

Explanation

We use the step-by-step process, where we start with the first derivative. We then apply the derivative of cos(x) to find the second derivative and simplify the terms to find the final answer.

Max from BrightChamps Praising Clear Math Explanations
Well explained 👍
Max, the Girl Character from BrightChamps

Problem 4

Prove: d/dx (2sin²(x)) = 4sin(x)cos(x).

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"
Okay, lets begin

Let’s start using the chain rule: Consider y = 2sin²(x) = 2(sin(x))²

To differentiate, we use the chain rule: dy/dx = 2·2sin(x)·d/dx [sin(x)]

Since the derivative of sin(x) is cos(x), dy/dx = 4sin(x)cos(x)

Substituting y = 2sin²(x), d/dx (2sin²(x)) = 4sin(x)cos(x) Hence proved.

Explanation

In this step-by-step process, we used the chain rule to differentiate the equation. Then, we replace sin(x) with its derivative. As a final step, we substitute y = 2sin²(x) to derive the equation.

Max from BrightChamps Praising Clear Math Explanations
Well explained 👍
Max, the Girl Character from BrightChamps

Problem 5

Solve: d/dx (2sinx/x)

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"
Okay, lets begin

To differentiate the function, we use the quotient rule: d/dx (2sinx/x) = (d/dx (2sinx)·x - 2sinx·d/dx(x))/x²

We will substitute d/dx (2sinx) = 2cosx and d/dx (x) = 1 = (2cosx·x - 2sinx·1)/x² = (2xcosx - 2sinx)/x² = (2xcosx - 2sinx)/x²

Therefore, d/dx (2sinx/x) = (2xcosx - 2sinx)/x²

Explanation

In this process, we differentiate the given function using the product rule and quotient rule. As a final step, we simplify the equation to obtain the final result.

Max from BrightChamps Praising Clear Math Explanations
Well explained 👍
Ray Thinking Deeply About Math Problems

FAQs on the Derivative of 2sinx

1.Find the derivative of 2sinx.

The derivative of 2sinx using the constant multiplication rule is: d/dx (2sinx) = 2cosx

Math FAQ Answers Dropdown Arrow

2.Can we use the derivative of 2sinx in real life?

Yes, we can use the derivative of 2sinx in real life to calculate the rate of change of any oscillatory motion, especially in fields such as physics and engineering.

Math FAQ Answers Dropdown Arrow

3.Is it possible to take the derivative of 2sinx at any point?

Yes, 2sinx is defined and differentiable at all points, so its derivative can be taken at any point.

Math FAQ Answers Dropdown Arrow

4.What rule is used to differentiate 2sinx/x?

We use the quotient rule to differentiate 2sinx/x, d/dx (2sinx/x) = (2xcosx - 2sinx)/x².

Math FAQ Answers Dropdown Arrow

5.Are the derivatives of 2sinx and sin(x) the same?

No, they are different. The derivative of 2sinx is 2cosx, while the derivative of sin(x) is cos(x).

Math FAQ Answers Dropdown Arrow
Professor Greenline from BrightChamps

Important Glossaries for the Derivative of 2sinx

  • Derivative: The derivative of a function indicates how the given function changes in response to a slight change in x.

 

  • Sine Function: A trigonometric function represented as sin(x).

 

  • Cosine Function: A trigonometric function that is the derivative of sin(x) and is represented as cos(x).

 

  • Constant Multiplication Rule: A rule stating that the derivative of a constant times a function is the constant times the derivative of the function.

 

  • Chain Rule: A rule used to differentiate composite functions.
Math Teacher Background Image
Math Teacher Image

Jaskaran Singh Saluja

About the Author

Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.

Max, the Girl Character from BrightChamps

Fun Fact

: He loves to play the quiz with kids through algebra to make kids love it.

INDONESIA - Axa Tower 45th floor, JL prof. Dr Satrio Kav. 18, Kel. Karet Kuningan, Kec. Setiabudi, Kota Adm. Jakarta Selatan, Prov. DKI Jakarta
INDIA - H.No. 8-2-699/1, SyNo. 346, Rd No. 12, Banjara Hills, Hyderabad, Telangana - 500034
SINGAPORE - 60 Paya Lebar Road #05-16, Paya Lebar Square, Singapore (409051)
USA - 251, Little Falls Drive, Wilmington, Delaware 19808
VIETNAM (Office 1) - Hung Vuong Building, 670 Ba Thang Hai, ward 14, district 10, Ho Chi Minh City
VIETNAM (Office 2) - 143 Nguyễn Thị Thập, Khu đô thị Him Lam, Quận 7, Thành phố Hồ Chí Minh 700000, Vietnam
UAE - BrightChamps, 8W building 5th Floor, DAFZ, Dubai, United Arab Emirates
UK - Ground floor, Redwood House, Brotherswood Court, Almondsbury Business Park, Bristol, BS32 4QW, United Kingdom