Is the 'Integer Function' Bound Valid for Given Functions f(t) and g(u)?

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given [x] the 'integer function' would be the following bound valid ??

[tex]\int_{0}^{\infty}dt [g(x/t)]f(t) \le \int_{0}^{\infty}dt g(x/t)f(t)[/tex]

for a given functions f(t) and g(u) u=x/t , here g is a non-decreasing positive function for positive arguments (and real) of parameter u=x/t
 
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Hi,

if f(t) >= 0 for t >=0, then using (g(x/t) + 1) would be a better idea ?
Now if
[tex]f(t) = f^{+}(t) - f^{-}(t)[/tex],
where [tex]f^{+}(t) and f^{-}(t)[/tex] denotes max(f(t),0) and max(-f(t),0) respectively
then one can use g(x/t) + 1 for f+(t) and g(x/t) - 1 for f-(t) to obtain a bound.