Question

sum inf k=1 (cos 1)^k diverge or converge if converge find the sum

Answer 1

\[\sum_{k=1}^{\infty} (\cos 1)^k\] so nobody can solve this then

Answer 2

I'm not sure if this is right, but I'll give it a shot.

Since cos(1) = 0, the sum is an infinite addition of zeros. So maybe the answer is that it converges to zero?

Answer 3

please do correct me if I'm wrong

Answer 4

close

Answer 5

true is converge but u need to use the geometry
formula

Answer 6

What is the geometry formula?

Answer 7

\[\sum_{n=1}^{\infty} ar^n-1= a+ar+ar^2+ar^3+... \] is converge if |r|<1 and its sum is \[\sum_{n=1}^{\infty} ar^n-1\]= a/1-r |r|<1 if |r|>=1 then is diverge

Answer 8

this the formula