Yikes! Help with a trigo sum please
Favorites|Homepage
Subscriptions | sitemap
HOME > > Yikes! Help with a trigo sum please

Yikes! Help with a trigo sum please

[From: ] [author: ] [Date: 12-03-07] [Hit: ]
2) Similarly, cos(x) + cos(y) = a,3) Dividing (1) by (2),So, x + y = either 90° or 450° [Since trigonometric functions are periodic functions,Substituting for y = 90° - x from the above,......
Given that sinx + siny = a, and cosx + cosy = a, where a is NOT equivalent to zero. Find sin x + cosx in terms of a

-
1) sin(x) + sin(y) = a
==> 2sin{(x+y)/2}*cos{(x-y)/2} = a [By sum/product relation]

2) Similarly, cos(x) + cos(y) = a, ==> 2cos{(x+y)/2}*cos{(x-y)/2} = a

3) Dividing (1) by (2),

tan{(x + y)/2} = 1

==> Either (x+y)/2 = 45° or 225°

So, x + y = either 90° or 450° [Since trigonometric functions are periodic functions, 450° is same as 90°]; thus x + y = 90°

4) We have sin(x) + sin(y) = a

Substituting for y = 90° - x from the above,
sin(x) + sin(90° - x) = a

==> sin(x) + cos(x) = a
1
keywords: please,trigo,Help,with,Yikes,sum,Yikes! Help with a trigo sum please
New
Hot
© 2008-2010 http://www.science-mathematics.com . Program by zplan cms. Theme by wukong .