I wonder why Sagemath is not able to solve this

var('x a b c') U_1 = lambda x, a, b, c: cxx^1+b*x+a show(LatexExpr(r'U(x) = '),U_1(x,a,b,c))

first order x derivative which must be positive

δU_1(x,a,b,c) = diff(U_1(x,a,b,c),x) assume(x>=0) solve_ineq([δU_1(x,a,b,c)>0],[x])

I wonder why Sagemath is not able to solve this

var('x a b c')
U_1 = lambda x, a, b, c: cxx^1+b*x+a
c*x*x^1+b*x+a
show(LatexExpr(r'U(x) = '),U_1(x,a,b,c))
 
first '),U_1(x,a,b,c))
#first order x derivative which must be positive
 
positive
δU_1(x,a,b,c) = diff(U_1(x,a,b,c),x)
assume(x>=0)
solve_ineq([δU_1(x,a,b,c)>0],[x])solve_ineq([δU_1(x,a,b,c)>0],[x])