Need help with a trigonometric expression

In summary, the problem is to prove that the expression ##\frac 1 2 (sin(2x)+1)## is equivalent to ##sin^2(x+\frac \pi 4)##. The solution involves using the trigonometric identity sin(a + b) = sin a.cos b + sin b.cos a and writing both expressions in terms of sin x and cos x. The reference provided may also be helpful for future problems involving trig identities.
  • #1
Adgorn
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Homework Statement


Just a simple problem, I need to take the expression##\frac 1 2 (sin(2x)+1)## and show it is equivalent to ##sin^2(x+\frac \pi 4)##, and I can't seem to manage to find the way to do so, so I would appreciate some insight.

Homework Equations


N/A

The Attempt at a Solution


Effectively messing around with the trigonometric identities to no avail.
 
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  • #2
You will need some relevant equations... N/A doesn't get you any further

And 'dunno' doesn't qualify as an attempt at solution.
 
  • #3
I do intend to help you with this really very simple problem, but I have to adhere to the rules (see PF guidelines ).
For starters: what do you get when you write out both in terms of ##\ \sin x\ ## and ##\ \cos x \ ## ?
 
  • #4
I guess I needed to write some identities there, sorry.
Following your comment I used sin (a + b) = sin a.cos b + sin b.cos a and got the wanted expression, thanks for the help.
 
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FAQ: Need help with a trigonometric expression

1. What is a trigonometric expression?

A trigonometric expression is a mathematical expression that involves trigonometric functions such as sine, cosine, and tangent. These functions are used to represent relationships between angles and sides of a triangle.

2. Why do I need help with a trigonometric expression?

Trigonometric expressions can be complex and involve multiple steps to simplify or solve. It is common for students to need help with these types of expressions, especially when they are first learning about trigonometry.

3. How do I simplify a trigonometric expression?

To simplify a trigonometric expression, you can use the trigonometric identities and rules, such as the Pythagorean identities and the sum and difference formulas. It is also helpful to convert all trigonometric functions to either sine or cosine.

4. Can you provide an example of a trigonometric expression?

One example of a trigonometric expression is sin(x) + cos(x). This expression involves two trigonometric functions and can be simplified using the sum formula for sine and cosine.

5. How can I use trigonometric expressions in real-life applications?

Trigonometric expressions are commonly used in fields such as engineering, physics, and astronomy to solve problems related to angles and distances. For example, they can be used to calculate the height of a building or the distance between two points using angles and side lengths.

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