For an isosceles triangle, the ratio of two angles with different sizes is 2:1, and the lengths of the three sides are 2 decimeters, 2 decimeters, and 2.83 decimeters respectively. What is the area of this triangle in square decimeters? ．
一个等腰三角形，量得大小不同的两个角度数之比为2：1，又量得三条边长度分别为2分米、2分米、2.83分米，这个三角形的面积是多少平方分米．
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">2 * 1</gadget>
<output>2</output>

<result>2</result>