设<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/c5f1cdd39e8149b69bfe9227dbc1ec8c.png?x-oss-process=image/sharpen,200"/>为<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/677f0bde95ae486a82cbb14872020e04.png?x-oss-process=image/sharpen,200"/>个已知的正数，则<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/98e3fe9beac64e57b67ebfc0b05333d0.png?x-oss-process=image/sharpen,200"/>（）。‌