You are Here: Home >< Maths

# C2 trig help Watch

1. (Original post by upthegunners)
I drew the graph but I not sure what I should be looking for that indicates a change in direction...

I guess it's because the negative time indicates the opposite direction and we only have 2 solutions, one positive and one negative?
No you sound a bit muddled. The change in direction occurs when the velocity moves from negative to positive.
2. (Original post by Mr M)
Yes if you just graph positive t. Alternatively you could integrate to find an expression for displacement and graph that.
I graphed +t and it's is just a steep line..
3. (Original post by Mr M)
No you sound a bit muddled. The change in direction occurs when the velocity moves from negative to positive.
Meh.. yea I am confused (Is this point I would be kicked out of your class Mr M? haha, jokes )

EDIT: In my GCSE class my Maths teacher called us "stupid" as we couldn't do something that her "1st years could do"
4. (Original post by upthegunners)
I graphed +t and it's is just a steep line..
Oh blimey! You misunderstood me.

I want you to graph the quadratic where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

How many times does the velocity change sign? This is the indicator of a change in direction.
5. (Original post by Mr M)
Oh blimey! You misunderstood me.

I want you to graph the quadratic where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

How many times does the velocity change sign? This is the indicator of a change in direction.
Do I just use any t values?
6. (Original post by upthegunners)
Do I just use any t values?
0 to 4 will do.
7. (Original post by upthegunners)
Solve:Attachment 208995

Okay so I draw my quadrant diagram like this:

Attachment 208996

thanks
If you're a visual person, draw the graph of y=cos2x, and then draw the line y=0.5 and see where it touches (might help you a little)?
8. (Original post by Mr M)
Oh blimey! You misunderstood me.

I want you to graph the quadratic where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

How many times does the velocity change sign? This is the indicator of a change in direction.
Hi Mr M

In the trig question I first posted about (from an exam paper) the question before it asked us to draw the graph of

Does this bare any significance to the next question? Have they included that question to help us with the next one?

Thanks
9. (Original post by upthegunners)
Hi Mr M

In the trig question I first posted about (from an exam paper) the question before it asked us to draw the graph of

Does this bare any significance to the next question? Have they included that question to help us with the next one?

Thanks
Yes that makes the next bit a little easier. You will see that there are two periods of the curve and that there are 4 solutions and their approximate values.
10. (Original post by Mr M)
Yes that makes the next bit a little easier. You will see that there are two periods of the curve and that there are 4 solutions and their approximate values.
thank you

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: April 15, 2013
Today on TSR

### Am I pregnant?

...or just paranoid?

### A robot wrote Harry Potter?

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.