Join TSR now and get all your revision questions answeredSign up now

C2 HELP

    • Thread Starter
    Offline

    2
    ReputationRep:
    show that (2 - cos^2 x) / (1 + sin^2 x) is equal to 1

    I have substituted cos^2 x by (1 - sin^2 x) but I don't know what to do next
    Offline

    2
    ReputationRep:
    (Original post by man111111)
    show that (2 - cos^2 x) / (1 + sin^2 x) is equal to 1

    I have substituted cos^2 x by (1 - sin^2 x) but I don't know what to do next
    2 - ( 1 - sin^2x) / (1 + sin^2x)

    After you expand the top bracket you will realise the signs change then u should be able to cancel

    Posted from TSR Mobile
    Offline

    3
    ReputationRep:
    (Original post by man111111)
    show that (2 - cos^2 x) / (1 + sin^2 x) is equal to 1

    I have substituted cos^2 x by (1 - sin^2 x) but I don't know what to do next

    https://www.symbolab.com/solver/step...7B2%7Dx%7D%3D1
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Rtdsv)
    2 - ( 1 - sin^2x) / (1 + sin^2x)

    After you expand the top bracket you will realise the signs change then u should be able to cancel

    Posted from TSR Mobile
    Thanks for replying, how would you expand it?
    Offline

    0
    ReputationRep:
    2-(1-sin^2)/1+sin^2
    2-1+ sin^2/1+sin^2
    1+sin^2/1+sin^2
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Super helper)
    2-(1-sin^2)/1+sin^2
    2-1+ sin^2/1+sin^2
    1+sin^2/1+sin^2
    hi, thanks for replying. I don't understand why -sin^2 changes to +sin^2
    Offline

    2
    ReputationRep:
    You basically have -1 outside the bracket so when expanding you get -1 x 1 which is -1 and -1 x -sin^2x which is +sin^2x since - x - give positive. Then 2-1+sin^2x

    Posted from TSR Mobile
    Offline

    0
    ReputationRep:
    (Original post by man111111)
    hi, thanks for replying. I don't understand why -sin^2 changes to +sin^2
    2-(1-sin^2)
    2-1--sin^2. 2 minuses Makes a plus

    U can write it as 2+(-1(1-sin^2)) if that helps you see it
    The minus doesnt only only act on the 1
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Rtdsv)
    You basically have -1 outside the bracket so when expanding you get -1 x 1 which is -1 and -1 x -sin^2x which is +sin^2x since - x - give positive. Then 2-1+sin^2x

    Posted from TSR Mobile
    thank you so much for helping me.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Super helper)
    2-(1-sin^2)
    2-1--sin^2. 2 minuses Makes a plus

    U can write it as 2+(-1(1-sin^2)) if that helps you see it
    The minus doesnt only only act on the 1
    Hi thanks for helping me.
 
 
 
Poll
Which party will you be voting for in the General Election 2017?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

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

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

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