calculus - Prove with the mean value theorem that $x-frac{x^2}{2} < ln(1+x)$

Prove with the mean value theorem that $x-\frac{x^2}{2}<\ln(1+x)$(0,\infty)$

Approach
$f(x) := \ln(1+x)$ with the mean value theorem in $[0,x]$

$\frac{1}{1+\xi}= \frac{\ln(1+x)-0}{x-0}$

$\frac{1}{1+\xi}$ takes the biggest value when $\xi$ is $0$

and so $1 <\frac{\ln(1+x)}{x}$ multiply with x and you get
$x<\ln(1+x)$

I can't prove the second part.

Answer

For MVT

$$\ln (1+x)+\frac{x^2}{2}-(\ln 1+0)=x\cdot\left(\frac{1}{1+c}+c\right)>x \quad c\in(0,x)$$

Indeed

$$\frac{1}{1+c}+c=\frac{c^2+c+1}{1+c}>1$$