what is the fastest most powerful commercial jet ?
current or past?
what do you mean by “powerful?” Highest speed carrying the most wait? Fastest speed but not necessarily able to Cary that much? Able to leap tall buildings in a single bound?
If you are talking about “to date” then the following might answer your question
Concorde: fastest ever
TU-144: close second for fastest ever
Douglas DC-8 fastest subsonic once (it did just over Mach 1 during testing)
Convair 990: fastest subsonic cruising speed
World’s fastest glider: Space Shuttle