integration of :-
1. x square divided by X raised to power 4 minus x square minus 12.

2. 1 minus cos x divided by cos x into 1 + cos x.

3. 1 over X + x square + x cube.

4. sin 2x over under root cos raise to power 4 x - sin square x.

5. under root 10 minus 4 x + 4x square

6. one over X + 1 into under root x square minus one.