Hi everyone. I've got a problem I can't solve and would love some help.

In an isosceles triangle, give an exact answer to the angle x, so that the area of the triangle is maximized. The angle x is adjacent to the base of the triangle.

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- June 5th 2009, 05:34 AMBurger kingisosceles triangle
Hi everyone. I've got a problem I can't solve and would love some help.

In an isosceles triangle, give an exact answer to the angle x, so that the area of the triangle is maximized. The angle x is adjacent to the base of the triangle. - June 5th 2009, 05:49 AMgreat_math
sorry, editing

- June 5th 2009, 05:51 AMGrandadArea of isosceles triangle
Hello Burger kingYou haven't said so, but I assume that the lengths of the equal sides remain constant as varies. If this is so, then let's assume that they are of length . Then:

Height of triangle =

Base of triangle =

So area of triangle,

Now you can use the identity , and say

And has a maximum value of when .

So there's your answer, .

Grandad - June 5th 2009, 06:07 AMBurger king
Thank you kindly :)