Some quick maths questions (on the day of my exam)

[SixT4]

My C2 Maths A-Level module is in a few hours and there's a few things that might come up that I'm not sure about.

The Trapezium Rule.
It's simple, but I'm still not sure how it works and I don't think I have any notes on it.

Trapezium = 1/2(h){(y0 + yn) + 2(y1 + y2 ... + yn)}
h = (a-b)/2

Say you have six values of x and y. Is h always the first value of x subtracted from the last all divided by 2? So if there's six values of x and y and the 6th value of x is 20 and the 1st is 0, h = 10, right (in the question I'm given a list of values)?

n = the number of coordinates? For 6 values of x and y the equation will be:

Trapezium = 1/2(h){(y0 + y5) + 2(y1 + y2 y3 + y4 + y5)}?
In the 2nd bracket do you just put in the values of y, except for y0 in sequential order and add them?


Logs
I can't remember how you change the base of a log. Formula and explanation, anyone?

Equation of a circle
If you're told to find the x coordinate(s) of where two circles touch/intersect, do you do it in the same way you'd find the intersection of two lines/curves? What do you do with the y^2 etc. in the equations?


I would've posted this in the Maths/Science forum, but there's only 5 viewing that compared to 48 viewing OOT [img]/images/graemlins/cool.gif[/img]

[kyro]

PM Kramer. Maybe he can help you.

[SixT4]

Awww. It got moved.

*curses mods* [img]/images/graemlins/wink.gif[/img]

[SixT4]

Got the answer now anyway. (apart from the circles touching, but meh).

[jthegreat]

[ QUOTE ]
If you're told to find the x coordinate(s) of where two circles touch/intersect, do you do it in the same way you'd find the intersection of two lines/curves? What do you do with the y^2 etc. in the equations?


[/ QUOTE ]

Put both equations in the form: y^2 = ....... then set the two right-hand sides equal and solve for x.

[SixT4]

You're a tad late, but thanks for the help anyway =P

That didn't come up anyway, but the trapezium rule came up.

I didn't think it'd be possible but it is.

Rllmukforum > 2+2

[img]/images/graemlins/blush.gif[/img]