Solve 5cos^2x - 10cosx +5 = 0 for x
Favorites|Homepage
Subscriptions | sitemap
HOME > > Solve 5cos^2x - 10cosx +5 = 0 for x

Solve 5cos^2x - 10cosx +5 = 0 for x

[From: ] [author: ] [Date: 12-04-13] [Hit: ]
Factor this like you would factor the quadratic u^2 - 2u + 1; it is a perfect square trinomial.Take the square root of both sides.Solve.Assuming solutions between 0 and 2pi,x = 0-Divide by 5.x = 2k pi,......
5cos^2x - 10cosx +5 = 0

please show your work or explain

-
5cos^2(x) - 10cos(x) + 5 = 0

Factor 5.

5(cos^2(x) - 2cos(x) + 1) = 0

Divide both sides by 5.

cos^2(x) - 2cos(x) + 1 = 0

Factor this like you would factor the quadratic u^2 - 2u + 1; it is a perfect square trinomial.

[cos(x) - 1]^2 = 0

Take the square root of both sides.

cos(x) - 1 = 0

Solve.

cos(x) = 1

Assuming solutions between 0 and 2pi,

x = 0

-
Divide by 5.

cos^2x - 2cosx + 1 = (cosx - 1)^2 = 0

cosx = 1

x = 2k pi, where k is any integer
1
keywords: cos,for,cosx,10,Solve,Solve 5cos^2x - 10cosx +5 = 0 for x
New
Hot
© 2008-2010 http://www.science-mathematics.com . Program by zplan cms. Theme by wukong .