The word(s) "investigate" appears 3 time(s) in 2 verse(s) in Quran in Saheeh International translation.

(1) O you who have believed, when you go forth [to fight] in the cause of Allah, investigate; and do not say to one who gives you [a greeting of] peace "You are not a believer," aspiring for the goods of worldly life; for with Allah are many acquisitions. You [yourselves] were like that before; then Allah conferred His favor upon you, so investigate. Indeed Allah is ever, with what you do, Acquainted.

(2) O you who have believed, if there comes to you a disobedient one with information, investigate, lest you harm a people out of ignorance and become, over what you have done, regretful.