6.&nbsp;設直線L : kx+ 3y +10= 0 &nbsp;與圓 &nbsp;C: x<sup>2</sup> +y<sup>2</sup> = 4 &nbsp;沒有交點，則常數k的範圍為何？&nbsp;<div>&nbsp;(A) &nbsp;−4&lt; k&lt;4 &nbsp; &nbsp; (B) − 2 &nbsp;&lt; k &lt;2</div><div>&nbsp;(C) −√2 &lt; &nbsp;k &lt; √2 &nbsp; &nbsp;(D) k &nbsp;&lt; −√2 或 k> √2 &nbsp;</div><div><br></div>