Transpose ‘gamma’ to create a family of curves —
gamma = [1, 1.2, 1.4, 1.6, 1.8, 2];
x = [0:0.01:2000];
b = 349.22567;
y = 2.*(gamma(:).^2 - x./b)
y = 6×200001
2.0000 1.9999 1.9999 1.9998 1.9998 1.9997 1.9997 1.9996 1.9995 1.9995 1.9994 1.9994 1.9993 1.9993 1.9992 1.9991 1.9991 1.9990 1.9990 1.9989 1.9989 1.9988 1.9987 1.9987 1.9986 1.9986 1.9985 1.9985 1.9984 1.9983
2.8800 2.8799 2.8799 2.8798 2.8798 2.8797 2.8797 2.8796 2.8795 2.8795 2.8794 2.8794 2.8793 2.8793 2.8792 2.8791 2.8791 2.8790 2.8790 2.8789 2.8789 2.8788 2.8787 2.8787 2.8786 2.8786 2.8785 2.8785 2.8784 2.8783
3.9200 3.9199 3.9199 3.9198 3.9198 3.9197 3.9197 3.9196 3.9195 3.9195 3.9194 3.9194 3.9193 3.9193 3.9192 3.9191 3.9191 3.9190 3.9190 3.9189 3.9189 3.9188 3.9187 3.9187 3.9186 3.9186 3.9185 3.9185 3.9184 3.9183
5.1200 5.1199 5.1199 5.1198 5.1198 5.1197 5.1197 5.1196 5.1195 5.1195 5.1194 5.1194 5.1193 5.1193 5.1192 5.1191 5.1191 5.1190 5.1190 5.1189 5.1189 5.1188 5.1187 5.1187 5.1186 5.1186 5.1185 5.1185 5.1184 5.1183
6.4800 6.4799 6.4799 6.4798 6.4798 6.4797 6.4797 6.4796 6.4795 6.4795 6.4794 6.4794 6.4793 6.4793 6.4792 6.4791 6.4791 6.4790 6.4790 6.4789 6.4789 6.4788 6.4787 6.4787 6.4786 6.4786 6.4785 6.4785 6.4784 6.4783
8.0000 7.9999 7.9999 7.9998 7.9998 7.9997 7.9997 7.9996 7.9995 7.9995 7.9994 7.9994 7.9993 7.9993 7.9992 7.9991 7.9991 7.9990 7.9990 7.9989 7.9989 7.9988 7.9987 7.9987 7.9986 7.9986 7.9985 7.9985 7.9984 7.9983
figure
plot(x, y)
grid
xlabel('X')
ylabel('Y')
legend("\gamma = "+string(gamma(:)), 'Location','best')

A slightly different version —
gamma = [1, 1.2, 1.4, 1.6, 1.8, 2].';
x = [0:0.01:2000];
b = 349.22567;
y = 2.*(gamma.^2 - x./b)
y = 6×200001
2.0000 1.9999 1.9999 1.9998 1.9998 1.9997 1.9997 1.9996 1.9995 1.9995 1.9994 1.9994 1.9993 1.9993 1.9992 1.9991 1.9991 1.9990 1.9990 1.9989 1.9989 1.9988 1.9987 1.9987 1.9986 1.9986 1.9985 1.9985 1.9984 1.9983
2.8800 2.8799 2.8799 2.8798 2.8798 2.8797 2.8797 2.8796 2.8795 2.8795 2.8794 2.8794 2.8793 2.8793 2.8792 2.8791 2.8791 2.8790 2.8790 2.8789 2.8789 2.8788 2.8787 2.8787 2.8786 2.8786 2.8785 2.8785 2.8784 2.8783
3.9200 3.9199 3.9199 3.9198 3.9198 3.9197 3.9197 3.9196 3.9195 3.9195 3.9194 3.9194 3.9193 3.9193 3.9192 3.9191 3.9191 3.9190 3.9190 3.9189 3.9189 3.9188 3.9187 3.9187 3.9186 3.9186 3.9185 3.9185 3.9184 3.9183
5.1200 5.1199 5.1199 5.1198 5.1198 5.1197 5.1197 5.1196 5.1195 5.1195 5.1194 5.1194 5.1193 5.1193 5.1192 5.1191 5.1191 5.1190 5.1190 5.1189 5.1189 5.1188 5.1187 5.1187 5.1186 5.1186 5.1185 5.1185 5.1184 5.1183
6.4800 6.4799 6.4799 6.4798 6.4798 6.4797 6.4797 6.4796 6.4795 6.4795 6.4794 6.4794 6.4793 6.4793 6.4792 6.4791 6.4791 6.4790 6.4790 6.4789 6.4789 6.4788 6.4787 6.4787 6.4786 6.4786 6.4785 6.4785 6.4784 6.4783
8.0000 7.9999 7.9999 7.9998 7.9998 7.9997 7.9997 7.9996 7.9995 7.9995 7.9994 7.9994 7.9993 7.9993 7.9992 7.9991 7.9991 7.9990 7.9990 7.9989 7.9989 7.9988 7.9987 7.9987 7.9986 7.9986 7.9985 7.9985 7.9984 7.9983
figure
plot(x, y)
grid
xlabel('X')
ylabel('Y')
legend("\gamma = "+string(gamma), 'Location','best')

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