Definite Integration — Easy JEE math MCQ$\int_0^1 x^3 dx$ equals:A. $\frac{1}{4}$B. $\frac{1}{3}$C. $1$D. $\frac{1}{2}$Solution$\int_0^1 x^3 dx = \left[\frac{x^4}{4}\right]_0^1 = \frac{1}{4} - 0 = \frac{1}{4}$