Suppose P(x):=xn+an−1xn−1+⋯+a1x+a0 is a monic polynomial of degree n≥1 (monic means that the coefficient of xn is 1).
a) Show that if n is even, then limx→∞P(x)=limx→−∞P(x)=∞.
b) Show that if n is odd, then limx→∞P(x)=∞ and limx→−∞P(x)=−∞ (see previous exercise).