$\lim_{x \to 1} \left[\dfrac{x-2}{x^2-x} - \dfrac{1}{x^3 - 3x^2 + 2x}\right] = $

If $A = \{1, 2, 3, 4, 5, 6\}$ then which of the following is not true?

Consider the following statements
$r$: If $p \rightarrow q$ is false then $p \vee q$ is false.
$s$: If $p \leftrightarrow q$ is false then $p \vee q$ is false.
The truth values of $r \rightarrow s$ and $s \rightarrow r$ are respectively ____

In triangle ABC, with usual notations, if the angles are in Arithmetic Progression and $3c^2 = 2b^2$, then the measure of angle A is