You are Here: Home >< Maths

# Trigonometrical identities question Watch

1. Could someone help me with this please!

Solve:
3SinƟ + TanƟ= 0

Thank you!
2. (Original post by Annabel_lear)
Could someone help me with this please!

Solve:
3SinƟ + TanƟ= 0

Thank you!

Multiply through by the denominator.
3. (Original post by Indeterminate)

Multiply through by the denominator.
So would that be:
3sin(theta) + = 0

Posted from TSR Mobile
4. (Original post by Annabel_lear)
So would that be:
3sin(theta) + = 0

Posted from TSR Mobile
5. (Original post by TenOfThem)
And then multiply by

Posted from TSR Mobile
6. (Original post by Annabel_lear)
And then multiply by

Yes

No
7. (Original post by TenOfThem)
Yes

No
Oh.. What would you do from there?

Posted from TSR Mobile
8. (Original post by Annabel_lear)
And then multiply by

Posted from TSR Mobile
factorize it
9. 0, pi, arccos(-1/3) these are the solutions in [0,2pi]
10. (Original post by ztibor)
factorize it
this
11. Sin theta (3 cos theta + 1 ) = 0

Now find solutions for Sin theta = 0

and 3 Cos theta = 0
12. (Original post by charly2012)
Sin theta (3 cos theta + 1 ) = 0

Now find solutions for Sin theta = 0

and 3 Cos theta = 0
To find solutions would you divide to the otherside? But wouldn't that just make 0?

Posted from TSR Mobile
13. (Original post by Annabel_lear)
To find solutions would you divide to the otherside? But wouldn't that just make 0?

Posted from TSR Mobile
Your solutions would be found within the equations:

and
14. (Original post by Annabel_lear)
And then multiply by

Posted from TSR Mobile
OK so you've got to this point:

Note that both terms on the LHS have a common factor so you can factorize it like this:

Now remember that if you multiply two things together and get zero, one of the things must be zero (or possibly both in some situations!).

So you can say that EITHER

OR

so you need to find solutions to each of these equations and then combine them to get a complete set of solutions to your original problem
15. (Original post by ztibor)
factorize it
Factorise with an 's'
16. (Original post by davros)
OK so you've got to this point:

Note that both terms on the LHS have a common factor so you can factorize it like this:

Now remember that if you multiply two things together and get zero, one of the things must be zero (or possibly both in some situations!).

So you can say that EITHER

OR

so you need to find solutions to each of these equations and then combine them to get a complete set of solutions to your original problem
Thank you! Great help

Posted from TSR Mobile

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.

This forum is supported by:
Updated: March 31, 2013
Today on TSR

### Falling in love with him

But we haven't even met!

### Top study tips for over the Christmas holidays

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• 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

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