XI is real science. As you move from 10 to XI as you see here also, the dialect as well as script changes!
Class X , as far as mathematics is concerned, is common mans maths, while for grade XI, it is building block of all science ahead.
Speaking quantitively, grade XI is 6 times grade 10 and hence shocker to every one. One chapter seems like half the course of class 10. If you go for JEE also, it becomes twice more difficult.
Don’t get disheartened. Its NOT the content but the sheer amount of course which makes the real difference. The number of different concepts are so vast that it makes life of student look like life of a ‘pi’ (Mathematically)!.
The load is more, but its worth bearing.