$\mathop {\lim }\limits_{x \to 0} \frac{x}{{\tan x}}$ is equal to

$\lim _{x}$ ${\rightarrow 0} \frac{\tan \left(\left[-\pi^2\right] x^2\right)-x^2 \tan \left(\left[-\pi^2\right]\right)}{\sin ^2 x}$ equals

$\lim _{x \rightarrow 0} \frac{1-\cos x}{x^2} = $

$\mathop {\lim }\limits_{x \to 0} \frac{{3\sin x - \sin 3x}}{{{x^3}}} = $

Evaluate the given limit: $\mathop {\lim }\limits_{x \to 0} \frac{\sin ax}{bx}$

$\mathop {\lim }\limits_{x \to 0} \frac{{2{{\sin }^2}3x}}{{{x^2}}} = $