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Sprendimas:
$$S_{1} = 4\cdot 1^{2}+4\cdot 1 = 4+4 = 8$$
Atsakymas: 8
Sprendimas:
$$S_{2n} = 4\cdot (2\cdot n)^{2}+4\cdot (2\cdot n)$$
$$S_{n} = 4\cdot n^{2}+4\cdot n$$
4* ( 2* n)^2+ 4* ( 2* n) =
* ( 4* n^2+ 4* n)
4* ( 2* n)^2+ 4* ( 2* n) = * ( 4* n^2+ 4* n)$$4\cdot (2\cdot n)^{2}+4\cdot (2\cdot n)$$ = $$\frac{11}{3}\cdot (4\cdot n^{2}+4\cdot n)$$ 16* n^2+ 4* ( 2* n) = * ( 4* n^2+ 4* n)$$16\cdot n^{2}+4\cdot (2\cdot n)$$ = $$\frac{11}{3}\cdot (4\cdot n^{2}+4\cdot n)$$ 16* n^2+ 8* n = * ( 4* n^2+ 4* n)$$16\cdot n^{2}+8\cdot n$$ = $$\frac{11}{3}\cdot (4\cdot n^{2}+4\cdot n)$$ 16* n^2+ 8* n = * 4* n^2+ * 4* n$$16\cdot n^{2}+8\cdot n$$ = $$\frac{11}{3}\cdot 4\cdot n^{2}+\frac{11}{3}\cdot 4\cdot n$$ 16* n^2+ 8* n = + * 4* n$$16\cdot n^{2}+8\cdot n$$ = $$\frac{44\cdot n^{2}}{3}+\frac{11}{3}\cdot 4\cdot n$$ 16* n^2+ 8* n = + $$16\cdot n^{2}+8\cdot n$$ = $$\frac{44\cdot n^{2}}{3}+\frac{44\cdot n}{3}$$ 16* n^2- + 8* n = $$16\cdot n^{2}-\frac{44\cdot n^{2}}{3}+8\cdot n$$ = $$\frac{44\cdot n}{3}$$ 16* n^2- + 8* n- = 0$$16\cdot n^{2}-\frac{44\cdot n^{2}}{3}+8\cdot n-\frac{44\cdot n}{3}$$ = $$0$$ + 8* n- = 0$$\frac{4\cdot n^{2}}{3}+8\cdot n-\frac{44\cdot n}{3}$$ = $$0$$ - = 0$$\frac{4\cdot n^{2}}{3}-\frac{20\cdot n}{3}$$ = $$0$$ n = 0$$n$$ = $$0$$
- = 0$$\frac{4\cdot n}{3}-\frac{20}{3}$$ = $$0$$ = 0+ $$\frac{4\cdot n}{3}$$ = $$0+\frac{20}{3}$$ = $$\frac{4\cdot n}{3}$$ = $$\frac{20}{3}$$ 4* n = $$4\cdot n$$ = $$\frac{20\cdot 3}{3}$$ 4* n = 20$$4\cdot n$$ = $$20$$
n = $$n$$ = $$\frac{20}{4}$$ n = 5$$n$$ = $$5$$
Atsakymas: n = 5
20 uždavinys22 uždavinys