例题3-2:畏缩一平移一翻转 ●x(如图所示, x(t) 求x(-2t-2) 压缩a=2→x(2) 2 右移b=1→x[2(t-1) ●翻转t→(4)>x(-2t2) X(-2t-2)=x[-2(t1)] =x[2(-1)
x(t) t -4 -2 0 1 2 2 例题3-2: 展缩-平移-翻转 ⚫ x(t)如图所示, 求x(-2t-2). ⚫ 压缩 a=2→ x(2t) ⚫ 右移 b=1→x[2(t-1)] ⚫ 翻转 t → (-t)→x(-2t-2) ⚫ x(-2t-2)=x[-2(t+1)] =x[2(-t-1)]