I really don't suppose that this will convince any muslim that the Quran is flawed, but one never knows. I believe that man's intellect is fallen, and has the capacity for infinite rationalisation and self-deception. Religion blinds the best of us. It can stare you in the face but if you believe something enough, the facts won't make a dent in it.
There are a number of apparent contradictions in the Quran. Whether they can be resolved is a matter for clever philosophers, the kind who can use a globe to prove that the earth is flat. Here is just one:
Did any of Noah's sons drown in the flood?
In Sura 11:41-43 it is written, "And as the Ark moved on with them amidst the mountainous waves, Nuh cried out to his son, who was apart: 'Embark with us, my child,' he said. 'Do not stay with the unbelievers!'
He said: 'I shall seek refuge in a mountain, which will protect me from the flood.'
He said, 'None shall be secure this day from Allah's judgment, except those to whom He will show mercy!' And thereupon the billows rolled between them, and he was drowned.
Here it is plain enough that one of Noah's sons drowned in the flood, according to the Qu'ran.
But in Sura 21:76 it is written: "And (remember Nuh). When he invoked Us, We heard his prayer, and We saved him and all his kinsfolk from the great calamity, and delivered him from the people who had denied Our revelations. Evil men they were; We drowned them all."
Thus in Sura 11 it is affirmed that one of Noah's sons drowned while in Sura 21 it is affirmed that they were all saved.