Răspuns:
[tex] \: a)(5 + 3x)(2x + 3) = > 5 \times 2x + 5 \times 3 + 3x \times 2x + 3x \times 3 = > 10x + 15 + 6x { }^{2} = > 6x {}^{2} + 10x + 15 \\ b) \: (a {}^{2} + b {}^{2} ) {}^{2} = > (a {}^{2} ) {}^{2} + 2a {}^{2} b {}^{2} + (b {}^{2} ) {}^{2} = > a {}^{4} + 2a {}^{2} b {}^{2} + b {}^{4} [/tex]
