add 4 each time
the nth term is a_n or f(n)
the next term after that is a_{n+1} or f(n+1)
so each term is 4 more than previous
basically
a_{n+1}=4+a_n or
f(n+1)=4+f(n)
same thing
1/(1/R1 + 1/R2 + 1/R3)
= 1/ (R2R3 + R1R3 + R1R2)/R1R2R3
= R1R2R3/ (R2R3 + R1R3 + R1R2)
Answer:
It is false that, if the national economy shrank at an annual rate of 9% per year for three consecutive years then the economy shrank by 27% over the 3-year period, because this percentage does not follow a linear path, but on the contrary, it is calculated exponentially: 9% of each year is calculated on the rest that remained after discounting 9% the previous year.
Thus, if the national economy has a value of 100, after three years it will not have a value of 79, but a value of 75.35, as it arises from the following calculation:
100 x 0.91 ^ 3 = X
100 x 0.753571 = X
75.35 = X
125x = 25
x = 0,2
There you go :)
