This identity is called the Sophomore's dream - in contrast to the name "Freshman's dream" which is given to the incorrect identity (x+y)ⁿ=xⁿ+yⁿ, this one has a similar too-good-to-be-true feel, but is true!
Someone: You should call the place and ask.
Me: I see an email address, I can send them an email.
Someone: But calling them would be faster.
Me: … I’ll send them an email.