Melody

Hi Gotcha,

During a race Ali ran the first 300 metres in 2 mins 10 secs and the last 100 metres in 30 secs. What was his average speed in m/s?

$$\\\frac{300+100metres}{2min+40seconds}\\\\
=\frac{400metres}{120+40seconds}\\\\
=\frac{400metres}{160seconds}\\\\
=\frac{5metres}{2seconds}\\\\
=2.5\;m/s$$

Thanks CPhill,

CPhill and I   have both interpreted your question to mean

$$y=tan^2x+tanx$$

If x=0 then y=0 because   tan0=0

If y=0 then

$$\\tanx(tanx+1)=0\\\\
tanx=0\;\;or\;\;tanx+1=0\\\\
sinx=0\;\;or\;\;tanx=-1\\\\
x=n\pi\pm \frac{\pi}{2}\;\;\;or\;\;\;x=n\pi\pm \frac{3\pi}{4}\qquad n\in Z$$

My answer is the same as CPhill"s

I think the 'enlargement' factor is     1/2

because the increase factor of the areas is   1/(2^2)   that is 1/4

The size has of course reduced - not enlarged.

You can enter it into this calc like this

nCr(5,4)

This is the output:

$${\left({\frac{{\mathtt{5}}{!}}{{\mathtt{4}}{!}{\mathtt{\,\times\,}}({\mathtt{5}}{\mathtt{\,-\,}}{\mathtt{4}}){!}}}\right)} = {\mathtt{5}}$$

This is undefined.

The number in the brackets must be between -1 and 1 inclusive.

The US kids are all on holidays MathsGod1, that is why it is so quiet.

I like it quiet, but I can certainly see your point of view :)

Thank you Fiora,

Yes maths is an international language but the words that are used around the maths are not :)