Inequality of integral : $\int_0^{1}((\sqrt{3}f(x))^{2}-2(f(x)^{3})dx≤1$

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If $f(x)>0$ be continue function then this inequality true ?

a) $\int_0^{1}((\sqrt{3}f(x))^{2}-2(f(x)^{3})dx≤1$

b) $(\int_0^{1}\sqrt{3}f(x))^{2}-\int_0^{1}2f(x)^{3}dx≤1$ I was used Cauchy Schwartz inequality but I don't get it

How I can learning integral inequality if any one have a good book tell me .

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If $3-2f(x)<0$, so it's obvious.

But for $3-2f(x)\geq0$ by AM-GM we obtain: $$\int\limits_0^1(3f(x)^2-2f(x)^3)dx\leq\int\limits_0^1\left(\frac{f(x)+f(x)+3-2f(x)}{3}\right)^3dx=1.$$ Because $$\int\limits_0^1\left(\left(\frac{f(x)+f(x)+3-2f(x)}{3}\right)^3-\left(3f(x)^2-2f(x)^3\right)\right)dx\geq0.$$