21. \( -\int(x-1)^{3} d x \) 22.- \( \int \frac{x}{x^{2}-1} d x \) 23.- \( \int \frac{4 x-3}{2 x^{2}-3 x-4} d x \) 24. \( -\int x^{2} \cdot e^{x^{3}} d x \) 25.- \( \int e^{2 x} d x \) 26. \( -\int 5^{3 x} d x \) 27. \( -\int \frac{\operatorname{sen} x}{5+e^{\cos x}} d x \) 28. \( -\int \sin 2 x d x \) 29.- \( \int x \cos x^{2} d x \) 30.- \( \int 4 \sin 5 x d x \)

21. \( -\int (x-1)^{3} \, dx = -\frac{(x-1)^{4}}{4} + C \) 22. \( -\int \frac{x}{x^{2}-1} \, dx = -\frac{1}{2} \ln |x^{2}-1| + C \) 23. \( \int \frac{4x-3}{2x^{2}-3x-4} \, dx = \frac{2}{3} \ln |2x+1| - \frac{1}{3} \ln |x-4| + C \) 24. \( -\int x^{2} e^{x^{3}} \, dx = -\frac{1}{3} e^{x^{3}} + C \) 25. \( \int e^{2x} \, dx = \frac{1}{2} e^{2x} + C \) 26. \( -\int 5^{3x} \, dx = -\frac{5^{3x}}{3 \ln 5} + C \) 27. \( -\int \frac{\sin x}{5 + e^{\cos x}} \, dx \) sin solución elemental 28. \( -\int \sin 2x \, dx = \frac{1}{2} \cos 2x + C \) 29. \( \int x \cos x^{2} \, dx = \frac{1}{2} \sin x^{2} + C \) 30. \( \int 4 \sin 5x \, dx = -\frac{4}{5} \cos 5x + C \)