# M3, M4, M5 Post here should you need help.Watch

#1
Good-day. Using the Pearson EdExcel books on each module to self-teach A-level Further Maths, very difficult. Since I don't wish to consume a thread for the purpose of answering one question, feel free to submit your own problems.

Having this issue with a lot of the questions in the book where the answers seem unfeasible given my working, though I am 90% confident given the Dunning-Kruger effect that such is the result of my incompetence. Anyhow here is the question;

(Exercise 3A): 1. A particle P of mass 0.2 kg is moving on the x-axis. At time t seconds P is x metres from the origin O. The force acting on P has magnitude 2costN and acts in the direction OP. When t = 0, P is at rest at O. Calculate

a the speed of P when t = 2,
b the speed of P when t = 3,
c the time when P first comes to instantaneous rest,
d the distance OP when t = 2
e the distance OP when P first comes to instantaneous.

The answers for the following questions being;
a 9.09 ms^-1 (3 s.f.)
b 1.41 ms^-1 (3 s.f.)
c P first comes to rest when t = pi
d 14.2 m (3 s.f.)
e OP = 20 m

My problem here is that following the given examples on the prior pages I could not get anything even remotely resembling the answers, personally I did the following;
> Used f = ma (2cost = 0.2a)
> Integrated on both sides leading to (-2sint + D = 0.2v, this is where I believe I have gone wrong)
> Used t = 0, v = 0, now I get completely stuck and cannot find an answer. The examples featured both a regular number and an exponential so it was easy to follow, though I cannot grasp what I am supposed to do next.
0
1 year ago
#2
(Original post by FalchionBetaMK)
...

Then plug in and for parts a,b. For c, set and find . For , integrate again and find the result at , then at the whatev your answer for c is.
1
#3
(Original post by RDKGames)

Then plug in and for parts a,b. For c, set and find . For , integrate again and find the result at , then at the whatev your answer for c is.
Thanks a ton for the help!
0
X

new posts
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

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

### University open days

• Cardiff University
Wed, 27 Mar '19
• University of Portsmouth
Wed, 27 Mar '19
• Middlesex University London
Wed, 27 Mar '19

### Poll

Join the discussion

#### How old were you when you first saw porn?

I've never seen it (122)
21.03%
Before I was 12 (200)
34.48%
13 (89)
15.34%
14 (70)
12.07%
15 (40)
6.9%
16 (17)
2.93%
17 (6)
1.03%
18 (5)
0.86%
Between the ages of 19 - 24 (7)
1.21%
Over 25 (1)
0.17%
12 (23)
3.97%