Kategorien
Rechnen

Termumformung

Regeln:

    \[ a+b = b+a\]

    \[ a-b = a +(-b) = -b + a \]

    \[ a+ b + c = a + (b+c) \]

    \[ a*(b+c) = a*b + a*c \]

    \[ a*b = b*a\]

    \[ a:b = a *\frac{1}{b} = \frac{1}{b} * a = \frac{a}{b}\]

Es gilt auch:

    \[  (a+b)*(c+d) = a*c+a*d+b*c+b*d \]

    \[  \frac{a}{b} + \frac{a}{c} = a*(\frac{1}{b} + \frac{1}{c}) \]

    \[  \frac{b}{a} + \frac{c}{a} = \frac{1}{a}*(b+c) \]

Beispiel 1

    \[2x^2 +4x+ 2 = 2*(x^2+2x+1) \]

    \[2x^3y +4x^2y+ 2xy \]

    \[= 2xy (x^2+2x+1)\]

Beispiel 2

Aus

    \[  (a+b)(c+d) = ac+ad+bc+bd \]

leiten sich die binomischen Formel ab:

    \[  (a+b)^2 = a^2 + 2ab + b^2\]

    \[  (a-b)^2 = a^2 - 2ab + b^2\]

    \[  (a+b)(a-b) = a^2 - b^2\]