Results are out! Find what you need...fast. Get quick advice or join the chat
Hey! Sign in to get help with your study questionsNew here? Join for free to post

Two simple C3 questions

Announcements Posted on
For applicants, undergrads and postgrads: Find out what's happening during Student Money Week here 05-02-2016
Are postgrad degrees a waste of time? Have your say and be in with a chance of winning a £30 Amazon voucher 29-01-2016
  1. Offline

    ReputationRep:
    Can someone explain these two questions to me as im not sure how they get to the answer.

    On question 8, when they say find the range, is it basically what value of x is needed to make f(x) positive?
    Click image for larger version. 

Name:	q8.png 
Views:	39 
Size:	25.5 KB 
ID:	151669

    On question 9c im not sure how they get to the answer. I understand the first part where they use the reciprocal from part bii but they last 3 parts i'm not sure if its random or intended .

    Click image for larger version. 

Name:	q9.png 
Views:	34 
Size:	53.5 KB 
ID:	151671

    Thanks in advance .
  2. Offline

    ReputationRep:
    They are not easy if you can't answer them though right?

    1st one: Draw the graph, its a basic stretch followed by a translation. The range previously would have been f(x)>0
    Therefore what will happen now?

    2nd one: cos^2y + sin^2y = 1
    siny = 2x
    Play with it from there
  3. Offline

    ReputationRep:
    (Original post by kozo)
    They are not easy if you can't answer them though right?

    1st one: Draw the graph, its a basic stretch followed by a translation. The range previously would have been f(x)>0
    Therefore what will happen now?

    2nd one: cos^2y + sin^2y = 1
    siny = 2x
    Play with it from there
    Thanks for your reply, i understand the first one, i'm just asking to confirm and the second one i'm still not entirely sure how to do.
  4. Offline

    ReputationRep:
    sin^y = 4x^2
    Its a C2 trig identity from there. You are simply trying to eliminate y from your expression.
  5. Offline

    ReputationRep:
    (Original post by kozo)
    sin^y = 4x^2
    Its a C2 trig identity from there. You are simply trying to eliminate y from your expression.
    Ok thank you i understand it now .

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. By joining you agree to our Ts and Cs, privacy policy and site rules

  2. Slide to join now Processing…

Updated: May 27, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

Today on TSR

Dropping out of Oxford

Find out what it's like in Ethereal World's blog

Poll
How much money do you spend a week at uni?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read here first

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups
Study resources
Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.