[m]e^{x}=1+x+\frac{x^2}{2}+\frac{x^3}{3!}+...[/m]
то
[m]e^{1,04} ≈ 1+1,04+\frac{1,04^2}{2}+\frac{1,04^3}{3!}[/m]
[m]e^{-1,04} ≈ 1-1,04+\frac{(-1,04)^2}{2}+\frac{(-1,04)^3}{3!}[/m]
[m]ch1,04 = \frac{e^{1,04}+e^{-1,04}}{2}[/m]
[m]ch1,04 ≈ \frac{1+1,04+\frac{1,04^2}{2}+\frac{1,04^3}{3!}+(1-1,04+\frac{(-1,04)^2}{2}+\frac{(-1,04)^3}{3!})}{2}=\frac{2+1,04^2}{2}=\frac{2+1,0816}{2}=1,5408[/m]