Sequences/Series
Convergence Tests
Convergence Tests Pt. 2
Power Series
Taylor/Maclaurin Series
100

Determine whether the sequence is convergent or divergent. If convergent what does is converge to?

a_n=(2+n^3)/(1+2n^3)

Converges to 

1/2

100

What are the requirements for integral comparison test

f(x) must be positive continuous and decreasing

100

Sigma_(n=1)^oo(3n^2+2)/(sqrt(4n^4+4))

Diverges by Divergence Test

100

Determine R and IOC

Sigma_(n=0)^oo(x^n)/(n!)

R=oo, I=(-oo,oo)

100

Use known Macluarin series to write as a Maclaurin Series

f(x)=sin(pix)

200

Determine convergence:

Sigma_(n=1)^oo 2^(2n+1)/5^n

converges to 

8

200

Sigma_(n=1)^oo((n^2+1)/(2n^2+1))^n

Converges by Root Test
200

Sigma_(n=1)^oo((-2)^n)/(n^2)

Diverges by Ratio or Root Test

200

Determine ROC and IOC

Sigma_(n=1)^oox^n/(2n-1)

R=1, IOC=(-1,1]

200

Use known Maclaurin Series to obtain a maclaurin series and it ROC

f(x)=e^x+e^(2x)

300

Determine convergence

2+0.5+0.125+0.03125+...

Converges to 

8/3

300

Sigma_(n=1)^oo (n^2+1)/(n^3+1)

Diverges by Limit Comparison Test

300

Sigma_(n=1)^oo(n!)/(100^n)

Diverges by ratio test

300

Find a power Series rep. and find IOC

f(x)=2/(3-x)

2/3 Sigma_(n=0)^oo(x/3)^n

R=3, I=(-3,3)

300

Find the Taylor Series and Radius

f(x)=e^(2x), a=3

R=oo

400

Determine convergence

Sigma_(n=1)^oo 1/(n(n+3))

Converges to 

11/18

400

Sigma_(n=1)^oo(cos^2(n))/(n^2+1)

Converges by Comparison Test

400

Sigma_(n=1)^oo((-1)^(n-1))/(n^(1/3))

Converges Conditionally

400

Find power series representation and determine the IOC:

f(x)=x/(9+x^2)

I=(-3,3)

400

Find taylor series centered at a

f(x)=cosx, a=pi

R=oo

500

Determine Convergence

Sigma_(n=1)^oo (1+2^n)/3^n

Convergence to 

5/2

500

Sigma_(n=1)^oo1/(nln(n))

Diverges by integral Test

500

Sigma_(n=2)^oo((-1)^nsqrtn)/(ln(n))

Fails AST b/c lim diverges to infinity. Diverges by divergence test.

500

Find power series representation and determine the IOC:

f(x)=x/(2x^2+1)

I=(-1/sqrt2,1/sqrt2)

500

f(x)=ln(x), a=2

R=2

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