Hello everyone.

Wish i could answer this question on my own,

The question is from october november 2008 AS level maths paper 1 exam paper

Question:

A wire, 80cm long is cut into two pieces. One piece is bent to form a square of side x cm and the other piece is bent to form a circle of radius r cm The total area of the square and circle is A cm^2

(i) show that A=

(pi+4)x^2 - 160x + 1600

-----------------------------

pi

I have no idea how to show that...

then the second question is just as difficult.

(ii) Given that x and r can vary, find the value of x for which A has a stationary value.

Would really love some help

Thanks

Peder