The three sides of a right triangle are 3cm, 4cm, and 5cm respectively. What is the area of this triangle in cm**2.
一个直角三角形的三条边分别是3cm、4cm、5cm，这个三角形的面积是多少cm**2．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<result>6</result>