The polynomial \(ax^3 - 10x^2 + bx + 8\), where \(a\) and \(b\) are constants, is denoted by \(p(x)\). It is given that \((x-2)\) is a factor of both \(p(x)\) and \(p'(x)\).
(a) Find the values of \(a\) and \(b\).
(b) When \(a\) and \(b\) have these values, factorise \(p(x)\) completely.
Find the quotient and remainder when \(8x^3 + 4x^2 + 2x + 7\) is divided by \(4x^2 + 1\).
Find the quotient and remainder when \(2x^4 + 1\) is divided by \(x^2 - x + 2\).