All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His Slave and Messenger.
Muslim scholars explained the meanings of these verses to eliminate anything that would seem to be a contradiction. Al-Haafith Ibn Katheer commented on the verse that reads (what means): {[He is] Lord of the Mashriqayn (two sunrises) and Lord of the Maghribayn (two sunsets).} He said, “The verse means the two sunrises of summer and winter and the two sunsets of summer and winter.” About the verse that reads (what means): {So, I swear by the Lord of [all] Mashaariq (risings) and Maghaarib (settings) that indeed We are able.}, he said, “The verse means the different risings and settings of the sun, as each day it has a new place where it rises and sets... As for the verse that reads (what means): {[He is] the Lord of the Mashriq and Maghrib (the rising and the setting)...}, it refers to the east and west in general.”
Thus it is clear that there is no contradiction between the verses. The Quran was revealed from Allaah, and since it is from Him, it can never include any contradiction or imbalance - praise be to Allaah; Allaah, The Exalted, says (what means): {Then do they not reflect upon the Quran? If it had been from [any] other than Allaah, they would have found within it much contradiction.} [Quran 4:82]
Allaah Knows best.