What is the angle between < 6 , 1 , -4 > <6,1,4> and < 2 , -3 , 2 > <2,3,2>?

1 Answer
Jan 28, 2016

88^@ 88

Explanation:

To find the angle between 2 vectors use the following formula :

costheta =( veca.vecb)/((|veca| xx |vecb|) cosθ=a.b(a×b)

where a and b represent the 2 vectors and
theta color(black)(" the angle between them") θ the angle between them

let veca = (6,1,-4) , vecb = (2 , - 3 , 2 ) a=(6,1,4),b=(2,3,2)

then veca . vecb = 12 - 3 - 8 = 1 a.b=1238=1

and |veca| = sqrt(6^2+1^2+(-4)^2) =sqrt(36+1+16) =sqrt53a=62+12+(4)2=36+1+16=53

|vecb| = sqrt(2^2+(-3)^2+2^2) = sqrt(4+9+4) = sqrt17 b=22+(3)2+22=4+9+4=17

hence costheta = 1/(sqrt53 xx sqrt17) cosθ=153×17

theta = cos^-1 (1/(sqrt901)) = 88^@θ=cos1(1901)=88