<p>So I have spent a month at my local publich unversity to conduct a mathematical research with my mentor, who really liked me but insisted me to go to his university because he said "undergrad doesn't matter, what matters is the grad schools". This past summer I did ask if he was willing to write me a rec to other universities and he said it was perfectly fine with him. But now I was debating if I should still let him to write my rec, even though I will apply to his university but what if he wanted me so bad and purposely write a bad rec to other schools? What should I do now?</p>
<p>If he is your mentor, and he likes you, he is not going to sabotage your college apps.</p>