信号与系统 奥本海默 习题答案 英文Exercise Ch. 11.1 Express each of the following complex numbers in Cartesian form (x+jy):(3) ejp/2 = cos(p/2)+j sin(p/2)=j(6)ejp/4 =[cos(p/4)+j sin(p/4)]=1+j1.2 Express each of the following complex numbers in polar form (r ejq, with -p< q £ p):(6) (1-j)2 = 1-2j + j2