设<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/32091c367ade4dbda4203b59af51aa0f.png?x-oss-process=image/sharpen,200"/>，则<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/0a2ca6cc87be447ab862cf8755764fe0.png?x-oss-process=image/sharpen,200"/>为函数<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/0a770eca6b76493a97709cdaf8dd0aec.png?x-oss-process=image/sharpen,200"/>的（）.