Join TSR now and get all your revision questions answeredSign up now
    • Thread Starter
    Offline

    3
    ReputationRep:
    Simplify sin(720-a).
    can someone please show me how they would attempt this question?
    Also please explain how you got your answer.
    Ty in advance
    • Community Assistant
    Offline

    19
    ReputationRep:
    Show your attempt and we will comment on it.
    Offline

    3
    ReputationRep:
    (Original post by bahjat93)
    Simplify sin(720-a).
    can someone please show me how they would attempt this question?
    Also please explain how you got your answer.
    Ty in advance
    \sin A=\sin \left (A +k\cdot 360\right )
    and
    \sin (-A)=-\sin(A)
    Offline

    0
    ReputationRep:
    Might help to draw a graph.
    • Study Helper
    Offline

    15
    ReputationRep:
    (Original post by bahjat93)
    Simplify sin(720-a).
    can someone please show me how they would attempt this question?
    Also please explain how you got your answer.
    Ty in advance
    Why have you classified this as undergraduate - it's basic A level stuff (if not GCSE)!

    Anyway, are you familiar with the periodic nature of the sine function, i.e. the way that it repeats itself after a certain period? Do you know the rules for working out sin(A+B) or sin(A-B)? Could you work out sin 360 for example?
    • Thread Starter
    Offline

    3
    ReputationRep:
    (Original post by davros)
    Why have you classified this as undergraduate - it's basic A level stuff (if not GCSE)!

    Anyway, are you familiar with the periodic nature of the sine function, i.e. the way that it repeats itself after a certain period? Do you know the rules for working out sin(A+B) or sin(A-B)? Could you work out sin 360 for example?
    Believe it or not, i did pretty well in my maths A-level but if you don't bloody study the subject for 9 months you tend to forget a thing or two :/
    • Study Helper
    Offline

    15
    ReputationRep:
    (Original post by bahjat93)
    Believe it or not, i did pretty well in my maths A-level but if you don't bloody study the subject for 9 months you tend to forget a thing or two :/
    OK, so see ztibor's post for the rules you need!
    Offline

    1
    ReputationRep:
    If you're still confused, note that sin(720-a)=sin(-a+360+360) .
 
 
 
Poll
Which pet is the best?
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.