Alan

Well done Bertie.  I forgot to sum the terms!!

Does this help?

It's not an equation (you haven't set it equal to anything) and it isn't quadratic (for which the x has to be raised to the power 2).  It does however have a quadratic factor, as it can be written as x³(3x² - 5).

Melody wrote: Is that a fact Alan? You definitely should know this

Actually, it's more of a hypothesis based on years of observation (I think someone from the automotive industry did tell me that once as well - a long time ago!) 

I guess your comment, that I should definitely know this, is based on my having spent my working life in Rolls-Royce.  However, R-R hasn't made cars since 1971, which is before I worked there!  I think the only part of a Rolls-Royce car actually owned by R-R these days is the doubleR logo, which is licensed out by R-R.

These are sin, cos, tan, cosec, sec and cot.

Deleted - See Bertie's answer below.

Yes, all the superscripts/subscripts were a bit of a pain, but no more so than typing \frac{}{} all the time in LaTeX!

Incidentally, I like your photo.  You look younger than I had expected!!

Virtually all car speedometers are deliberately overclocked, usually by between 5% and 10% (to judge by comparisons with roadside speed warning indicators), to make you think you are going slightly faster than you are!

As Anonymous has noted, this is an expression not an equation.  However, notice that it factors nicely into (x+3)(x-2), so if you wanted to find the values of x that make the expression equal zero, you can see immediately that those values would be x = -3 and x = 2.