有關A-Maths(M1)的問題~~~(10)點~~~

1) Expand [e^(3x) +e^(-x)] / e^(2x) as a series in ascending powers
of x as far as the term in x^3.
2) Solve e^(x+1) - e^(x) = 1
3) If $P is invested in a bank , it will accumulate to $2P after 15 years.
Find the interest rate per annum if the interest is compounded
a) quarterly
b) continuously
4) In 2009,an environmentalist claims that the average yearly temperature
T°C of a city t years later is given by T = 25e^(kt). K is a constant.
In 2014,the average yearly temperature of the city is 25.8°C.
a) Find the value of k
b) Based on the value obtained in (a),find the average yearly temperature
of the city in 2039.

本人初學，請詳細一點~!