3.
[tex]\sqrt{2}(5\sqrt{2}-6)+3(4-2\sqrt{2})-22 = \sqrt{2}\cdot5\sqrt{2}-\sqrt{2}\cdot6 + 3\cdot4 -3\cdot2\sqrt{2}-22 =\\\\=10-6\sqrt{2}+12-6\sqrt{2}-22 = -12\sqrt{2}\\\\Odp. \ b)[/tex]
4.
[tex](3x^{2}-4)(2x^{2}+6) = 3x^{2}\cdot2x^{2}+3x^{2}\cdot6-4\cdot2x^{2}-4\cdot6 = 6x^{4}+18x^{2}-8x^{2}-24 =\\\\=6x^{4}+10x^{2}-24\\\\Odp. \ a)[/tex]
