I'm clueless about how to solve this question, please show step by step.
A circular disc of metal has a radius of xcm. When it is heated to a particular temperature it expands and the radius of xcm increases by 2cm. When it has cooled to a particular temperature it contracts and the radius of xcm is decreased by 2cm.
Show that the difference between the area when it has heated and the area when it has cooled, is 8xpi.
This is an extension question my teacher gave me, I'm not sure what to apply.
A circular disc of metal has a radius of xcm. When it is heated to a particular temperature it expands and the radius of xcm increases by 2cm. When it has cooled to a particular temperature it contracts and the radius of xcm is decreased by 2cm.
Show that the difference between the area when it has heated and the area when it has cooled, is 8xpi.
This is an extension question my teacher gave me, I'm not sure what to apply.