Zadanie 28 Wzór, z którego skorzystamy to: [latex]a_2-a_1=a_3-a_2[/latex] a) [latex]x+2-(x-1)=2x-1-(x+2)[/latex] [latex]x+2-x+1=2x-1-x-2[/latex] [latex]3=x-3[/latex] [latex]x=6[/latex] b) [latex]x+2-(x-2)=3x-4-(x+2)[/latex] [latex]x+2-x+2=3x-4-x-2[/latex] [latex]4=2x-6[/latex] [latex]2x=10[/latex] [latex]x=5[/latex] c) [latex]2x-4-(3x+1)=5x+3-(2x-4)[/latex] [latex]2x-4-3x-1=5x+3-2x+4[/latex] [latex]-x-5=3x+7[/latex] [latex]-4x=12[/latex] [latex]x=-3[/latex] d) [latex]7-x=19-7[/latex] [latex]7-x=12[/latex] [latex]-x=5[/latex] [latex]x=-5[/latex] Zadanie 31 a) [latex]r=a_2-a_1=7-2=5[/latex] [latex]a_n=a_1+r(n-1)=2+5(n-1)=2+5n-5=5n-3[/latex] b) [latex]r=-6-(-3)=-6+3=-3[/latex] [latex]a_n=a_1+r(n-1)=-3-3(n-1)=-3-3n+3=-3n[/latex] c) [latex]r=7-1=6[/latex] [latex]a_n=a_1+r(n-1)=1+6(n-1)=1+6n-6=6n-5[/latex] d) [latex]r=7,6-8=-0,4[/latex] [latex]a_n=a_1+r(n-1)=8-0,4(n-1)=8-0,4n+0,4=-0,4n+8,4[/latex]
