x Turn on thread page Beta
 You are Here: Home >< Maths

# C3 - Iteration watch

1. When it says suitable starting value what do I use? part 3b
Also for 5ii. The way you work out alpha is saying tan alpha = b/a
Is b=-1 or 1?
Attached Images

2. your iteration graph sort of resembles a square root graph, but flipped about the y axis.

Start the iterations at x=1 Convergence is pretty rapid.
Attached Images
3. 2nd.pdf (13.1 KB, 126 views)
4. 5 2) eh? alpha is roughly 14 degrees...
5. (Original post by Hasufel)
5 2) eh? alpha is roughly 14 degrees...
Yh I got that as well but is it Rcos(x-14)=2 or Rcos(x+14)=2?
Because when I use the first one I get a different answer from the markscheme
6. 2nd one, because when you work out R, R is

and the angle is

it works out that way because of the minus sign in the expansion:

cancels itself out when you do the tan thing. (you DO usually pay attention to what quadrant it`s in, and here, it WOULD be in the 4th (180 deg+14.03..) - but the question specifies a range..

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: January 26, 2015
Today on TSR

### Negatives of studying at Oxbridge

What are the downsides?

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