I just took a hair drug test. Smoked marihuana daily up until 100 days ago. Hair was taken from armpit which was trimmed to 1-1.5 inches. Will I pass?

Impossible to say. Axillary hair growth rate varies a lot from person to person. In a little over 3 months, you may have grown the hair more than 1 1/2 inches, but it's just as likely you did not. Stay clean and you will eventually pass.
Tests vary. Time will tell. It's too late to change your part in it, so wait and see. I've heard rumors that range from 90 days through 18 months. You'll actually know soon about your specific case. Good luck. Take care.
May not. Canshow use for up to 6 months. Best way to pass is not to use at all.