A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Hello, what method is being used to expand this expression?

  • This Question is Open
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    1 Attachment
  2. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    they wrote 2a as a+a where a in this case is e^(x+y) similarly for -2 e^(-x-y) they then introduced e^(y-x) - e^(y-x) (which adds to zero) and similarly e^(x-y) - e(x-y)

  3. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I guess my real question is where did e^(y-x) - e^(y-x) and e^(x-y) - e^(x-y) come from or were they just added arbitrarily?

  4. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I guess they are aiming to use Euler's formula https://en.wikipedia.org/wiki/List_of_trigonometric_identities#Relation_to_the_complex_exponential_function to write the expression in terms of sin and cos

  5. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Except they're not complex functions. The first line simplifies to sinh (x+y), the hyperbolic sine. The second line is equivalent to the first line. What's the context? When extra terms are added that cancel each other, the purpose is usually to regroup the terms, in this case to get the sum of two or more groups of terms.

  6. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.