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Integration maths question.

How would you approach this question in this Maths paper, and if you can, please explain to me why.
It is from the OCR exam board, Core 2: June 2008 Question 5 part (I).
And can be found here: http://www.ocr.org.uk/Images/63180-question-paper-unit-4722-core-mathematics-2.pdf

Reply 1

username1732491

Original post by BlossomSerena

Find x as a function of y.

Find limits using function.

Integrate.

Reply 2

square_peg

First I would find the y values of the two horizontal lines (by finding the points of intersection with the curve), say y1 and y2.

Then I would think about the integral as two regions: the region where you want to integrate x from 0 to 2 and y from y1 to y2, and the region where you want to integrate between the curve and the line y=y2.

Find the curve as a function of y (so y=2+root(x+2) => x=f(y)), and write both integrals as [integral from y1 to y2] [some integral over x domain] *** dx dy

Then when you work out the middle part "[integral over x domain] *** dx" you can incorporate the two integrals over y together.