You are Here: Home >< Maths

# Maths (Trapezium rule) watch

1. Use the trapezium rule with four ordinates (three strips) to find an approximate value for?
Integral (limits 3-0) sqrt(2^x) dx

(How do you find the width of first and second strip, 1st height, sum of mid heights and find the last height, with no diagram)

Also when would you sub the limits into the integral and then minus them?

Thanks
2. Well, the integral is between 3 and 0, so the strips are going to be between these values of x, so the strips will be 0-1,1-2,2-3, each with a width of 1. The height will be the output of f(x)=sqrt(2^x) for the first x value of each strip, ie h_1=sqrt(2^0)
I don't know what you mean for the sum of mid heights, and the last height you can find the same way as the first.
I'd assume then you find the area of each strip and sum them to get your approximation.
There is a formula for the trapezium rule though.
Something like 1/2h(h_0 +h_n 2(h_1 + ... + h_n-1))..
(i can;'t remember exactly)
Though you could just integrate that one.

I think that makes sense, though I've already made some pretty stupid errors today, so I may have done that again.

I think that's right, so your answer should be something close to that.

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: September 27, 2010
Today on TSR

### Medicine offers

Find out which unis send them quickest

### University open days

• Sheffield Hallam University
Wed, 17 Oct '18
• Staffordshire University
Wed, 17 Oct '18
• Teesside University
Wed, 17 Oct '18
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