您可以通過發表評論的方式提問題, 我如果有時間就會思考, 並給出答案的鏈接.
如果您學過Latex, 發表評論的時候請直接輸入Latex公式; 反之, 請直接上傳圖片 (掃描、拍照、mathtype編輯), 發表評論的最后一個按鈕 
即可實現.
另外, 如果是書上的題目, 請給出哪本書; 如果是哪個學校的考研題, 也請注明是哪個學校哪年的, 並請通過郵件 zhangzujin361@163.com 發給我試題. 其他情形就不要發表評論了.
評論1與評論2已經給出了示例.
You may just post a question in this webpage, and I shall think about it if I have time, and I will link the answer to it.
If you know Latex, you may just type it in latex form (after doing this, just click 
);
otherwise, you may just upload the picture (have you seen the last icon in posting a comment? Just click it and upload your png,jpg or gif files which are generated by mathtype software or others).
I would be very appreciated if you point out the references you are doing.
Good luck then.