Simplify Trigonometric Expression

In summary, the original trigonometric expression can be simplified to 1/cos^2θ by cancelling out the common term sinθ and applying the identity sin^2θ + cos^2θ = 1. This simplification can be verified by using the identities cscθ = 1/sinθ, tanθ = sinθ/cosθ, and secθ = 1/cosθ.
  • #1
pbonnie
92
0

Homework Statement


Simplify the following trigonometric expression:
cscθtanθsecθ


Homework Equations


tanθ = sinθ/cosθ
sin^2θ + cos^2θ = 1
cscθ = 1/sinθ
secθ = 1/cosθ
cotθ = 1/tanθ

The Attempt at a Solution


I just want to double check my solution.
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ
= sin^2θ x 1
= sin^2θ

Thank you!
 
Physics news on Phys.org
  • #2
pbonnie said:

Homework Statement


Simplify the following trigonometric expression:
cscθtanθsecθ


Homework Equations


tanθ = sinθ/cosθ
sin^2θ + cos^2θ = 1
cscθ = 1/sinθ
secθ = 1/cosθ
cotθ = 1/tanθ

The Attempt at a Solution


I just want to double check my solution.
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
You're OK to here, but not below. Why not simplify by doing some cancelling?
pbonnie said:
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ
= sin^2θ x 1
= sin^2θ

Thank you!
 
  • #3
pbonnie said:
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ

What you have above isn't incorrect, but it isn't helpful, either. I don't know how you got the line that follows (sin^2θ x 1) from this.
 
  • #4
Hmm okay would I cancel out the sinθ in 1/sinθ x sinθ/cosθ x 1/cosθ so it simplifies to 1/cos^2θ?
 
  • #6
Oh okay. Thanks :)
 

FAQ: Simplify Trigonometric Expression

What is a trigonometric expression?

A trigonometric expression is an algebraic expression that contains one or more trigonometric functions, such as sine, cosine, tangent, or their inverses. These expressions are commonly used in mathematics, physics, and engineering to model and solve real-world problems involving angles and triangles.

How do I simplify a trigonometric expression?

To simplify a trigonometric expression, you can use various trigonometric identities and properties, such as the Pythagorean identities, double angle formulas, and sum and difference formulas. You can also use algebraic techniques, such as factoring, to reduce the expression to a simpler form.

Why is it important to simplify trigonometric expressions?

Simplifying trigonometric expressions can make them easier to work with and understand. It can also help you solve equations and problems more efficiently. In addition, simplifying expressions can reveal patterns and relationships between different trigonometric functions, which can be useful in further mathematical and scientific applications.

What are some common mistakes when simplifying trigonometric expressions?

One common mistake is not using the correct trigonometric identities or properties. Another mistake is not factoring out common terms or using incorrect algebraic steps. It is also important to be aware of any restrictions on the values of the variables in the expression, such as avoiding division by zero.

How can I practice simplifying trigonometric expressions?

You can practice simplifying trigonometric expressions by working through examples and problems in textbooks, online resources, or with a tutor. It can also be helpful to create your own practice problems and check your solutions with a calculator or by working backwards from the simplified expression.

Similar threads

Back
Top