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3 unit maths HELP (1 Viewer)

s09mcleandu

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Hey everyone,
I had a 3 unit math test today, and i couldn't do half of it.
Have u got ne good ways of remembering the properties for circle geometry etc. It was also on all of the prelim 2u but harder.
If u can help out or send some study notes, throw them my way and that will be heaps gd.

Thanx heaps
 

solomarc20

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Circle theroems come with heaps of practise. The best way to remember circle theorems is grouping them. I remember my theorems under four headings

Angles
Chords
Tangents
Cyclic Quadrilaterals

U'll find lots of ppl screw up their 1st 3U test (I almost failed mine...) Once you get used to the demands of the topic, u'll definitely improve!
 

gloworm14

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write and draw diagrams for all the properties in a 'summary'
that may help you in keeping them all in a neat pile to remember
 

Aplus

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solomarc20 said:
I remember my theorems under four headings
Angles
Chords
Tangents
Cyclic Quadrilaterals
Same here.
 

foram

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solomarc20 said:
Circle theroems come with heaps of practise. The best way to remember circle theorems is grouping them. I remember my theorems under four headings

Angles
Chords
Tangents
Cyclic Quadrilaterals

U'll find lots of ppl screw up their 1st 3U test (I almost failed mine...) Once you get used to the demands of the topic, u'll definitely improve!
o, oops, my method is much more crude. Circle theorems are just a giant tangle inside my head, i just happen to remember the right ones when i need to. :D
 

m&ss2008

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if the question doesnt accompany a diagram, feel free to draw one up yourself and mark what you're trying to find.
depending on how many marks its worth you may even gain one or two marks for doing this.
remember to use every piece of information.
they wouldnt give you it if you didnt need it

plus, if you cant even start it, have a go anyway. you might stumble upon it or get marks for showing a basic understanding.

to get full marks take the advice of those who've posted above me.

practice makes average. more practice makes pretty good. even more practice makes perfect.:D
 

bored of sc

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Inequalities with the pronumeral in the denominator (our school's way):
> Multiply each side by the denominator squared.
> Rearrange the equation so everything is equal to zero.
> Factorise (possible).
> Solve for the pronumeral (either through factorisation, quad formula etc) like you are solving an equation.
> Check that one of your factorisation brackets is the denominator with the pronumeral - this is always the case. The value of this expression cannot not be zero as you can't divide by 0.
> Substitute a number into the equation that is not one of the values you got for the above answer(s).
> If the statement is true for the equation the solution lies within that range of numbers; whether it be larger or smaller than the values for the pronumerals you got.
> Check again if in doubt.
This way is probably different to what you learn - but this way is very logical for me.

Circle theroms:

Arcs and Chords
1) Equal arcs subtend equal angles at the centre of the cirlce.
2) Equal chords subtend equal angles at the centre of the circle.

Angles
3) The angle at the centre of the circle is twice the circumference subtended by the same arc.
4) Angles in the same segment of a circle are equal.
5) The angle in a semi-circle is a right-angle.

Chords
6) A perpendicular line from the centre of a circle to a chord bisects the chord.
7) Equal chords are equidistant from the centre of the circle.
8) The intersection of two chords: if two chords of the same circle intersect the product of the two linear parts created by one chord is equal to the product of the two linear parts created by the other chord. (if that makes sense)

Cyclic Quadrilaterals
9) The opposite angles in a cyclic quadrilateral are supplemantary (add to 180 degrees).
10) The exterior angle of a cyclic quadrilateral is equal to the interior and opposite angle.

Tangents
11) The tangent to circle is perpendicular to the radius from the point of contact.
12) The tangents to a circle from an exterior point are equal.
13) When two circles touch, the line through their centres passes through their point of contact.
14) The angle between a tangent and a chord through the point of contact is equal to the angle in the alternate segment.
15) The square of the length of the tangent from the exterior point is equal to the product of the secant passing through this point - PQ^2 = QR.QS where PQ is a tangent to the circle.

Hope that helps. You probably know it all anyway. Just send me a PM if you can't understand how I use my language (as it barely makes sense) and any of this stuff and I'll give you some examples/better explaination (well, I'll try to).

As everyone else said, practise is parmount - its better to know how to do examples/questions and get them right then know all the theroms off by heart and not know how to apply them to questions.

Good luck with it all.
 
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F-O-B

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Has anyone found the topic - permutations and combinations - in the cambridge 3 unit? I can't seem to find it, looking at the contents it's not there...
 

dada1988

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combination and permutation are in Cambridge Year 12 3 unit....like the last chapter i think
 

Aerath

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F-O-B said:
Has anyone found the topic - permutations and combinations - in the cambridge 3 unit? I can't seem to find it, looking at the contents it's not there...
Can't find it in Year 11 Cambridge.
 

F-O-B

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dada1988 said:
combination and permutation are in Cambridge Year 12 3 unit....like the last chapter i think
Yeah thanks, just checked page 415 for P and 427 for C.

Aerath said:
Can't find it in Year 11 Cambridge.
Yeah it's not in it, I checked the index. And there's only 2 pages on that topic in the year 12 book. Strange considering J.B fitzpatrick has a whole chapter dedicated to it...
 
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what i do is write my theorms on the mirror so the always there
and as some1 said b4 maths needs alo of pratice
 

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