If $\lim\limits _{x \rightarrow 1} \frac{\sin \left(3 x^{2}-4 x+1\right)-x^{2}+1}{2 x^{3}-7 x^{2}+a x+b}=-2$,then the value of $(a-b)$ is equal to

The product of all possible values of $\alpha$, for which $\lim_{x \to 0} \left( \frac{1 - \cos(\alpha x) \cos((\alpha + 1)x) \cos((\alpha + 2)x)}{\sin^2((\alpha + 1)x)} \right) = 2$, is:

For $\alpha, \beta, \gamma \in R$,if $\lim _{x \rightarrow 0} \frac{x^2 \sin(\alpha x) + (\gamma-1) e^{x^2}}{\sin(2x) - \beta x} = 3$,then $\beta + \gamma - \alpha$ is equal to:

If $\mathop {\lim }\limits_{x \to 0} \frac{{[(a - n)nx - \tan x]\sin nx}}{{{x^2}}} = 0,$ where $n$ is a non-zero real number,then $a$ is equal to

Evaluate the value of $k$ if $\lim _{x \rightarrow 0} \frac{(7^x-1)^4}{\tan (\frac{x}{k}) \cdot \log (1+\frac{x^2}{3}) \cdot \sin 4 x} = 3(\log 7)^3$.

If $\lim _{x}$ ${\rightarrow \infty} \frac{(\sqrt{2 x+1}+\sqrt{2 x-1})^8+(\sqrt{2 x+1}-\sqrt{2 x-1})^8(P x^4-16)}{(x+\sqrt{x^2-2})^8+(x-\sqrt{x^2-2})^8} = 1$,then $P=$