Låt $A,B,C$ och $D$ vara punkter i rummet (dimension irrelevant). Vilken vektor motsvarar följande linjärkombination (oberoende på vad punkterna är)?
$$ \overrightarrow{BD} + \overrightarrow{CD} + 2\overrightarrow{BC} + 2\overrightarrow{DB} + \overrightarrow{CB} $$
Typing functional expressions
Functional expressions are largely written as by hand. Functions must
be written with parentheses: i.e. sin(x), not sin x.
sqrt(x) exp(x)abs(x)
Exponents are written using ^: e.g. $2^{x+y}$ is wrtten as 2^(x+y).
Place parentheses where needed: $\dfrac{x+y}{1+x}$ is written as (x+y)/(1+x)
Multiplication sign may but do not have to be explicitly written out:
$x\cdot y$ may be written as xy or x*y.