A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

arindameducationusc

  • one year ago

Without calculator,steps for finding cos inverse(8/208)?

  • This Question is Closed
  1. amilapsn
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    \[\arccos{\frac{8}{208}}=\arccos{\frac{1}{26}}=\frac{\pi}{2}-\arcsin{\frac{1}{26}}\approx \frac{\pi}{2}-\frac{1}{26}\]because for small \(\theta\), \(\sin\theta=\theta\Rightarrow\arcsin\theta=\theta \)

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

    Answer had to come in degrees which is 88 @amilapsn .. Please proceed again...

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

    please do all in steps.... Till I get 88 degrees

  4. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Nice! @arindameducationusc are you saying you don't know how to convert \(\frac{\pi}{2}-\frac{1}{26}\) from radians to degrees ?

  5. amilapsn
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    \[\arccos{\frac{8}{208}}\approx\frac{\pi}{2}-\frac{1}{26}=\left(\left(\frac{\pi}{2}-\frac{1}{26}\right)\times \frac{180}{\pi}\right)^o\approx88^o\]

  6. amilapsn
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    Are you ok @arindameducationusc ?

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

    It should be (pi/2-1/26)*pi/180.... @amilapsn @ganeshie8

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

    No, I got it....my bad..... silly mistakes do happen! LOL...!!!! I got it@amilapsn

  9. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    whichever you're converting to, that must be on top : radians to degrees : 180/pi degrees to radians : pi/180

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

    Thank you. one question @ganeshie8 why did we use pi/2-arcsin(theota)?????

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

    property? Send me a link about this property?

  12. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    familiar with this identity \(\arcsin(x)+\arccos(x)=\frac{\pi}{2}\) ?

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

    o yes, got it...! thank you.....

  14. ganeshie8
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    np :) you also need to know the small angle approximation of \(\sin\theta\) when \(\theta\) is small, we can replace \(\sin\theta \) by \(\theta\)

  15. 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.