Calculation: QTva7L - 1

cos(α) =

( x1* x2* y1* y2)

/ ( saknis(

x1^²* y1^²)* saknis(

x2^²* y2^²))

cos(α) =

( x1* x2* y1* y2)

/ ( saknis(

x1^²* y1^²)* saknis(

x2^²* y2^²))

$cos(\alpha)$ = $\frac{x1\cdot x2\cdot y1\cdot y2}{\sqrt {x1^{2}\cdot y1^{2}}\cdot \sqrt {x2^{2}\cdot y2^{2}}}$

cos(α) = 1 $cos(\alpha)$ = $1$

α = 0 $\alpha$ = 0