Alan

Speed = frequency*wavelength

You haven't given the units of length!

If we assume wavelength = 300 m then, with frequency = 10⁶ s^-1 

$${\mathtt{speed}} = {{\mathtt{10}}}^{{\mathtt{6}}}{\mathtt{\,\times\,}}{\mathtt{300}} \Rightarrow {\mathtt{speed}} = {\mathtt{300\,000\,000}}$$ m/s

Anonymous is correct:

$${{log}}_{{\mathtt{0.8}}}{\left({\mathtt{0.25}}\right)} = {\mathtt{6.212\: \!567\: \!439\: \!010\: \!781}}$$

$${{\mathtt{0.8}}}^{{\mathtt{6.212\: \!567\: \!439\: \!010\: \!781}}} = {\frac{{\mathtt{1}}}{{\mathtt{4}}}} = {\mathtt{0.249\: \!999\: \!999\: \!999\: \!999\: \!9}}$$

15a² - 3a = 3 - 7a

Add 7a to both sides

15a² + 4a = 3

Subtract 3 from both sides

15a² + 4a - 3 = 0

This factorizes nicely:

(3a - 1)*(5a + 3) = 0

So a = 1/3  and a = -3/5

It isn't never ending but it has 607 decimal digits. Here they are

2²⁰¹⁴=1881097331137338612503073916809514162622165323102118216462569860015335442665259522222750902380963872634381868464517059008015759705478029855008245933943444578945105742156796395531284957564764895173491539805200158634501987756382426954912842154647000743459307463608932742085748811458532338066000514612761930651142863404801368155789385479092863941032915378183028780510521357607272581238559232684216613000269112917940574914593124841200091826747034554393245932485051874026372428326333186689598782787037275467864152892763767038416466516695974781074067878443132930874335703872681455957081545994439636601225697296384

I've taken this notation to mean the nearest integer that is greater than or equal to x.

e.g. if x = 2.1 then [[x]] = 3

if x = 1 then [[x]] = 1 

if x = -1.5 then [[x]] = -1

The graph of the function below might help

The volume of a cube of side length L is L³, so L = ³√216 = 6 cm

The area of one face of the cube is L² =36 cm²

You can work out the total area of all the faces from that. 

Here's a (slightly simplified) explanation/example.

Does that help any?

I'll answer by drawing some graphs:

Perhaps this graph might help: