If you had ever read the entire Quran it says this :
Q 5:73
لَّقَدْ كَفَرَ الَّذِينَ قَالُواْ إِنَّ اللّهَ ثَالِثُ ثَلاَثَةٍ وَمَا مِنْ إِلَـهٍ إِلاَّ إِلَـهٌ وَاحِدٌ وَإِن لَّمْ يَنتَهُواْ عَمَّا يَقُولُونَ لَيَمَسَّنَّ الَّذِينَ كَفَرُواْ مِنْهُمْ عَذَابٌ أَلِيمٌ
"Indeed those have disbelieved who said "Verily Alllah is the third of three", and nothing is there of a G-d except one G-d, and if they do not cease from what their saying indeed a horrifying penalty will befall those among them"
The Quran makes a distinction of the true believers and unbelievers amongst Christians. The Quran makes this very clear who true Jews, Christians, and Sabeans are and have recounted many Christians who did not believe in trinity, Jesus as the son of G-d, or Jesus being G-d whom were noted as the true believers.