Cut out the largest circle from a square piece of paper with a side length of 3 cm. What is the area of the cut part in square centimeters?
用一个边长3厘米的正方形纸片剪下一个最大的圆，剪去的那部分面积是多少平方厘米．
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) ** 2</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">3.14 * (9/4)</gadget>
<output>7.065</output>

<gadget id="calculator">9 - 7.065</gadget>
<output>1.935</output>

<result>1.935</result>