Question

設(shè)y=f(t)是某港口水的深度y(米)關(guān)于時(shí)間t(時(shí))的函數(shù),其中0≤t≤24,下表是該港口某一天從0時(shí)至24時(shí)記錄的時(shí)間t與水深y的關(guān)系:

T	0	3	6	9	12	15	18	21	24
Y	12	15.1	12.1	9.1	11.9	14.9	11.9	8.9	12.1

經(jīng)長(zhǎng)期觀察,函數(shù)y=f(t)的圖象可以近似地看成函數(shù)y=k+Asin(ωt+φ)的圖象,下面的函數(shù)中,最能近似表示表中數(shù)據(jù)間對(duì)應(yīng)關(guān)系的函數(shù)是(    )

A.y=12+3sint,t∈［0,24］                 B.y=12+3sin(t+π),t∈［0,24］

C.y=12+3sint,t∈［0,24］                D.y=12+3sin(t+),t∈［0,24］

Answer 1

解析:根據(jù)時(shí)間t與水深的關(guān)系,畫(huà)出y=f(x)的圖象.

A==3,k==12,T=12,ω==.

∴y=3sint+12,t∈［0,24］.

答案:A