Homework Help: CALCULUS

Posted by JESSICA on Monday, October 15, 2007 at 9:31pm.

I got this problem but its unrelated to any material that we worked on. Can some please help me to solve it and please explain it. Thanks
Problem states:
Given:
x+(1/x)= square root of 3

PROVE:
(x^13)+(1/(x^13))= square root of 3

CALCULUS - Count Iblis, Monday, October 15, 2007 at 9:53pm
Put x = exp(i t)

Then:

x + 1/x = 2 cos(t)

x + 1/x = sqrt(3) ---->

cos(t) = sqrt(3)/2 ---->

t = ąpi/6 (adding a multiple of 2 pi leaves x invariant)

x^(13) + x^(-13) = 2 cos(13 t) =

2 cos(13/6 pi) = 2 cos(pi/6) = sqrt(3)
CALCULUS - bobpursley, Monday, October 15, 2007 at 10:00pm
solve for x in the given equation using the quadratic equation. Then, describe it on the complex plane, a vector at 60deg.

But x^13 is the same value, rotated around the plane twice. 13*60=60 +n360

QED

Answer this Question

Related Questions

Calculus - Hi there I am having some troubles trying to do my calculus homework ...
math - A material has a half-life of 12 hours. If initially there are 4 grams of...
Pre-Calculus - I have to use the substitution method to solve the system of ...
calculus - I am working on this problem and having some trouble. We're ...
Calculus - 1/a+1 + 1/a-1 I solved this out by multiplying the (a+1) by (a-1) and...
Math - Jo's mother bought some fabric in a sale.She bought 2 1/2m white,3 1/...
algebra - Solve the formula for the variable given. P = r-c/n solve for c. (...
Math subject Calculus - Hi there I am having some difficulties to solve this ...
Pre Calculus Repost Please Help - Can someone help me solve this problem: cos^2x...
Algebra - I have this math probelm z-(3z)/(2-z)=(6)/(z-2) in my book it says to ...

For Further Reading

First Name:
School Subject:
Answer: