Given that \(81\times 2^{2n-2} = K, find \sqrt{K}\)

Simplify \(\frac{4}{x+1}-\frac{3}{x-1}\)

If y varies inversely as x\(^2\), how does x vary with y?

If \(tan x = \frac{1}{\sqrt{3}}\), find cos x - sin x such that \(0^o \leq x \leq 90^o\)

From the top of a cliff 20m high, a boat can be sighted at sea 75m from the foot of the cliff. Calculate the angle of depression of the boat from the top of the cliff