What is the sum from k=1 to infinity of (cos(18))^k ?

The sum from k=1 to infinity of (cos(18))^k is converges

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

sum from k=1 to infinity of (cos(18))^k

k = 1 \sum \infty (cos (18))^{k}

converges

Solution steps

k = 1 \sum \infty (cos (18))^{k}

n = k \sum \infty (a_{n}) = n = 0 \sum \infty (a_{n}) - a_{0} - a_{1} - \dots a_{k - 1}

= k = 0 \sum \infty (cos (18))^{k} - (cos (18))^{0}

k = 0 \sum \infty (cos (18))^{k} =

converges

= converges - (cos (18))^{0}

= converges

n = 0 \sum \infty (sin (9))^{n}

n = 2 \sum \infty \frac{n}{( ln ( n ) ) n}

n = 1 \sum \infty \frac{n}{n ^{3} + n}

k = 1 \sum \infty 90 (0.1)^{k}

n = 0 \sum \infty \frac{4}{9 - n}

What is the sum from k=1 to infinity of (cos(18))^k ?
The sum from k=1 to infinity of (cos(18))^k is converges