41.As a actor, he can perform, sing, dance and play several kinds of musical instruments A flexible灵活的,柔韧的 n flexibility B. versatile形容人多才多艺的,形容工具用途广泛的vers代表随时可以变换的n. versatility DVD= Diaital versatile disc
Question: Are there sets of basic\ signals so that a) We can represent rich classes of signals as linear combinations of these building block signals b) The response of ltI Systems to these basic signals are both simp and insightful Fact: For LtI Systems(CT or dt) there are two natural choices for these building blocks Focus for now:
Text Understanding of Text A Text Organization Language Points Useful Expressions Sentences to Be Remembered Exercises Background Information Text Understanding of Text B Text Organization Language Points Useful Expressions Sentences to Be Remembered Exercises Background Information Grammar Focus Grammatical Points Exercises Communicative Activities Listening Communicative Expressions Learn to Communicate
Fourier series: Periodic signals and lti Systems ()=∑H(k k= ak一→H(ko)ak “g Soak-→|H(jkco)lkl H(7k)=1H(k0e∠B(ko) or powers of signals get modified through filter/system ncludes both amplitude phase akeJhwon