当电阻R上的<img src="/lqwvjeImg/53/532d5b956cdc43489921324d8cd809f1.png"style="width:17px;height:20px;">、<img src="/lqwvjeImg/15/153d2e97a520e414b42b4fc558cc47a5.png"style="width:12px;height:22px;">参考方向为非关联时,欧姆定律的表达式应为()<br>·<img src="/lqwvjeImg/ce/ce92bf22e911f0ea3bbafe544b41c34b.png"style="width:60px;height:25px;"><br>·<img src="/lqwvjeImg/6a/6a8e82f0182822bc06dfabaa7f3efa3c.png"style="width:73px;height:25px;"><br>·<img src="/lqwvjeImg/b7/b784cf1f81fb0a1f06ddebeca6f79fca.png"style="width:78px;height:36px;">