Question

A sequence is defined recursively using the formula f(n + 1) = –0.5 f(n) . If the first term of the sequence is 120, what is f(5)?

Answer 1

@hartnn

Answer 2

@eliassaab

Answer 3

helpp

Answer 4

please, note that, from data of your text, I can write this:
\[f(2)=-\frac{ 1 }{ 2 }f(1)=-\frac{ 1 }{ 2 }*120=-60\]

Answer 5

\[f(3)=-\frac{ f(2) }{ 2 }=\frac{ -60 }{ 2 }=-30\]

Answer 6

the way i put it is the right way there is no difference

Answer 7

oops..f(39=-(-60/2)=30

Answer 8

f(3)=30

Answer 9

\[f(4)=-\frac{ f(3) }{ 2 }=-\frac{ 30 }{ 2 }=-15\]

Answer 10

finally:
\[f(5)=-\frac{ f(4) }{ 2 }=-\frac{ -15 }{ 2 }=\frac{ 15 }{ 2 }\]

Answer 11

another one plssss

Answer 12

ok!

Answer 13

we have:
\[f(290f(1)-8=100-8=92\]

Answer 14

oops..f(2)=f(1)-8=100-8=92

Answer 15

f(3)=f(2)-8=92-8=84

Answer 16

f(4)=f(3)-8=84-8=76

Answer 17

f(5)=f(4)-8=76-8=68

Answer 18

finally:
f(6)=f(5)-8=68-8=...
please complete the computation

Answer 19

60

Answer 20

that's right!