For the numbers a, b, c, d stipulate <a, b, c, d>=2ab-((d)/(c)), known <1, 2, 3, x>=2, then x=what ．
对于数a，b，c，d规定＜a，b，c，d＞=2ab-((d)/(c))，已知＜1，2，3，x＞=2，则x=多少．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / (1/3)</gadget>
<output>6</output>

<result>6</result>