Q: How to write the first paragraph in the rationale of research?
The rationale of your research is the reason for conducting the study or the justification for your study. Usually, the rationale is a part of the introduction section. In the introduction, you should first give a background on what research has do far been done on your topic. Begin with general information about your research area and the gradually narrow it down to provide more specific information. Finally get down to your topic and give an idea of what research has been done on this topic and what is missing. This is the "gap in research" that your study will address. Then explain what specifically you are going to do to address this gap.
Thus, the rationale of your research should begin by identifying the gap in research that your study will address. Explain the gap in the literature and emphasize why it is important to address this gap. This will form the rationale of your study. The rationale should be followed by a hypothesis and objectives.