##### 4.25.42 $$y''(x)-2 y'(x)+y(x)=50 \cos (x) \cosh (x)$$

ODE
$y''(x)-2 y'(x)+y(x)=50 \cos (x) \cosh (x)$ ODE Classiﬁcation

[[_2nd_order, _linear, _nonhomogeneous]]

Book solution method
TO DO

Mathematica
cpu = 0.259697 (sec), leaf count = 41

$\left \{\left \{y(x)\to e^{-x} \left (-4 \sin (x)+\left (3-25 e^{2 x}\right ) \cos (x)+e^{2 x} (c_2 x+c_1)\right )\right \}\right \}$

Maple
cpu = 0.395 (sec), leaf count = 34

$[y \left (x \right ) = \textit {\_C2} \,{\mathrm e}^{x}+{\mathrm e}^{x} \textit {\_C1} x +\left (3 \cos \left (x \right )-4 \sin \left (x \right )\right ) {\mathrm e}^{-x}-25 \,{\mathrm e}^{x} \cos \left (x \right )]$ Mathematica raw input

DSolve[y[x] - 2*y'[x] + y''[x] == 50*Cos[x]*Cosh[x],y[x],x]

Mathematica raw output

{{y[x] -> (E^(2*x)*(C[1] + x*C[2]) + (3 - 25*E^(2*x))*Cos[x] - 4*Sin[x])/E^x}}

Maple raw input

dsolve(diff(diff(y(x),x),x)-2*diff(y(x),x)+y(x) = 50*cos(x)*cosh(x), y(x))

Maple raw output

[y(x) = _C2*exp(x)+exp(x)*_C1*x+(3*cos(x)-4*sin(x))*exp(-x)-25*exp(x)*cos(x)]