Chapter 1 - Vectors - 1.2 Length and Angle: The Dot Product - Exercises 1.2 - Page 30: 43

($\frac{3}{2}, \frac{-3}{2},\frac{3}{2},\frac{-3}{2}$)

u = (1,-1,1,-1) , v = (2, -3. -1. -2) Proju(v) =( $(u∙v)/(u∙u) )*u$ u∙v= 1*2+-3*-1 +1*-1 + 1*-2 = 2 + 3 -1 +2 = 6 u∙u= 1+ 1 + 1 + 1 = 4 $\frac{6}{4}$ = $\frac{3}{2}$ $\frac{3}{2}$ * u = ($\frac{3}{2}, \frac{-3}{2},\frac{3}{2},\frac{-3}{2}$)