Can I have a magic bow as my pact weapon without getting the Improved Pact Weapon Eldritch Invocation?

Question

The Warlock's Pact of the Blade feature specifies that you can only create melee weapons, but you can also turn a magic weapon into your pact weapon (without specifying that it's only melee weapons). Can I have a magic bow as my pact weapon without getting the Improved Pact Weapon Eldritch Invocation?

Answer 1

Concerning magic weapons, the Pact of the Blade option for the Pact Boon feature says (PHB, pg. 108):

You can transform one magic weapon into your pact weapon by performing a special ritual while you hold the weapon.

The qualifying word “melee” is notably absent, so you may perform the ritual to make a magical bow your pact weapon; the improved pact weapon invocation is not necessary.

As user RevenantBacon pointed out in comments, this is explained in further detail in the Sage Advice Compendium (p. 6 of the PDF):

If a warlock uses Pact of the Blade to bond with a magic weapon, does that weapon have to be a melee weapon, and can the warlock change the weapon’s form?

[...]

You can also use Pact of the Blade to bond with a magic weapon, turning it into your pact weapon. This magic weapon doesn’t have to be a melee weapon, so you could use the feature on a +1 longbow, for instance.

[...]