Question: Evaluate the limits below. If a limit does not exist state why

a) \(\underset{x\to -1}{\mathop{\lim }}\,\) (x^3 + 2x^2 - 3X -4)

b) \(\underset{x\to 2}{\mathop{\lim }}\,\) (x^3-8)/2-x)

c) \(\underset{x\to \infty }{\mathop{\lim }}\,\) (4x^3 + 6x - 3) / 4-3x^2

d) \(\underset{x\to {{0}^{+}}}{\mathop{\lim }}\,\) sin(2x)-4 / x +sin(3x)