AT THE END è IN THE END

AT THE END è IN THE END

At the end è in the end èìåþò ðàçíûå çíà÷åíèÿ.

At the end (of something) — â òî âðåìÿ, êîãäà ÷òî-òî êîí÷àåòñÿ.
At the end of the month — â êîíöå ìåñÿöà
At the end of the match — â êîíöå ìàò÷à
At the end of the concert there was applause. — Â êîíöå êîíöåðòà áûëè àïëîäèñìåíòû.
Àíòîíèì at the end — at the beginning — â íà÷àëå

In the end — "â êîíöå êîíöîâ"
We had a lot of problems with our car. In the end we sold it and bought another one. — Ó íàñ ñ ìàøèíîé áûëî ìíîãî ïðîáëåì. Â êîíöå êîíöîâ, ìû åå ïðîäàëè è êóïèëè äðóãóþ.