[_quadrature]
Book solution method
Missing Variables ODE, Dependent variable missing, Solve for
Mathematica ✓
cpu = 0.00319314 (sec), leaf count = 24
Maple ✓
cpu = 0.007 (sec), leaf count = 20
DSolve[x^2*y'[x]^2 == a^2,y[x],x]
Mathematica raw output
{{y[x] -> C[1] - a*Log[x]}, {y[x] -> C[1] + a*Log[x]}}
Maple raw input
dsolve(x^2*diff(y(x),x)^2 = a^2, y(x),'implicit')
Maple raw output
y(x) = a*ln(x)+_C1, y(x) = -a*ln(x)+_C1