问道国外的数学题(t)n(T)=500*0.81 The function above can be used to model the population of a certain endangered species of animal. If n(t) gives the number of the species living t decades after the year 1900, which of the following is true ab
问道国外的数学题(t)n(T)=500*0.81 The function above can be used to model the population of a certain endangered species of animal. If n(t) gives the number of the species living t decades after the year 1900, which of the following is true ab
问道国外的数学题
(t)
n(T)=500*0.81
The function above can be used to model the population of a certain endangered species of animal. If n(t) gives the number of the species living t decades after the year 1900, which of the following is true about the population of the species from 1900 to 1920 ?
详细写下做的过程
小t在0.81上 （t)
写错了是，n(T)=500*0.81
着是选者
1.It increased by about 1,000.
2.It increased by about 320.
3.It decreased by about 180.
4.It decreased by about 320.
5.It decreased by about 1,000.
最后答案是3
问道国外的数学题(t)n(T)=500*0.81 The function above can be used to model the population of a certain endangered species of animal. If n(t) gives the number of the species living t decades after the year 1900, which of the following is true ab
1900年时,t=0,
n(t)=500*0.81^0=500
1920年时,t=2,
n(t)=500*0.81^2=500*0.81*0.81=328.05 约328只
所以是减少了 500-328＝182只.
答案3是减少了大约180只,所以是答案3.
n(t)是这种生物生活的年代超过1900的年数除以10的数,有次题可知,n(t)为2.
所以由公式可知.n(T)=500*0.81的二次方,也就是说n(T)=500*0.81*0.81=328.05
路过,看看洋玩意儿