Vectors a and b are such that the magnitude of a = magnitude of b and the angle between a and b is 40 degress. The angle between vectors a and a + b is?

Thanks for the help!

Printable View

- Nov 12th 2006, 02:28 AMclassicstringsVectors
Vectors a and b are such that the magnitude of a = magnitude of b and the angle between a and b is 40 degress. The angle between vectors a and a + b is?

Thanks for the help! - Nov 12th 2006, 02:40 AMearboth
Hello, classicstrings,

do the addition of vectors geometrically. Because $\displaystyle \|{\vec{a}}=\|{\vec{b}}$ you'll get a rhombus. Thus the vector $\displaystyle \vec{a}+\vec{b}$ bisect the angle. So the value of the angle you are looking for is 20°.

EB - Nov 12th 2006, 03:08 AMclassicstrings
dankeschön! My german exam is tommorrow :D, then maths on Wednesday, then chinese on thursday!