Hallo,
3a
\( \begin{aligned} & 3 b^{3}\left(4 b^{2}-5 b^{5}\right) \\=& 12 b^{5}-15 b^{8} \\=& 3 b^{5} \cdot\left(4-5 b^{3})\right.\end{aligned} \)
3b
\( x^{n-3}\left(x^{5}+x^{4}\right)= \)
\( x^{n-3+5}+x^{n-3+4}= \)
\( x^{n+2}+x^{n+1}= \)
\( x^{n} \cdot x^{2}+x^{n} \cdot x^{1}= \)
\( x^{n+1}(x+1) \)
3c
\( \begin{aligned} &\left(4 a^{5}+3 b^{3}\right)\left(2 a^{3}-2 b\right) \\=& 2 a^{8}-4 a^{5} b+6 a^{3} b^{3}-6 b^{4} \end{aligned} \)
3c
\( \begin{aligned} &\left(3 x^{5} y^{2}\right)^{2} \\=& 9 x^{10} y^{4} \end{aligned} \)
4a
\( \begin{aligned} &(5 x-2)^{2}-(3-4 x)^{2}-(4-x)(4+x) \\=& 25 x^{2}-20 x+4-\left(9-24 x+16 x^{2}\right)-\left(16-x^{2}\right) \\=& 25 x^{2}-20 x+4-9+24 x-16 x^{2}-16+x^{2} \\=& 10 x^{2}+4 x-21 \end{aligned} \)
4b
\( \begin{aligned} &(6 a-b)^{2}+(6 a-b)(6 a+b)-(6 a+b)^{2} \\=& 36 a^{2}-12 a b+b^{2}+36 a^{2}-b^{2}-\left(36 a^{2}+12 b+b^{2})\right.& \\=& 72 a^{2}-12 a b-36 a^{2}-12 a b-b^{2} \\=& 36 a^{2}-24 a b-b^{2} \end{aligned} \)
Gruß, Silvia
