pardon my ignorance

but i was trying to solve a simple integral

following that video on youtube

https://www.youtube.com/watch?v=aw_VM_ZDeIo

but then at the moment 3:34 he states that

**x/sqr(x) is equal to sqrt(x)**

which i obviously believe

i typed x/sqrt(x) in wolfram alpha and it also gave me the result

**sqrt(x)**

but i don't understand why

could any of you folks prove it to me in a (or more than one) simple explanation?

Thanks a lot!