Maths, Addmaths and Statistics: Post your doubts here!

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

Since they are congruent polygons, ABD = 40 +40
=80

thanks buddy but plz explain little more this part confusion

 

[intelnehalem]

Re: O'level Maths, Addmaths and Statistics help available he

Since they are congruent polygons, ABD = 40 +40
=80

thanks buddy but plz explain little more this part confusion

Sure! Ok now, both of those polygons are the same, meaning the interior and exterior angles are also the same!
We can do this in an easier way : Since the 2 obtuse angles (ABC and the other one ) are equal to each other [congruency] , 360=140+140+ABD (angles at a point is equal to 360)
therefore 360-280= ABD
ABD= 80

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

yeah that was easy one thanks

 

[intelnehalem]

Re: O'level Maths, Addmaths and Statistics help available he

yeah that was easy one thanks

No problem ! Feel free to ask more questions dude :beer:

 

[floral123]

Re: O'level Maths, Addmaths and Statistics help available he

Actually its a question from EDEXCEL IGCSE MATHS SP Paper but at forum their, no one replying me so plz help me in this with steps:

 

[roneyms]

Re: O'level Maths, Addmaths and Statistics help available he

@ Floral,

given y=5x+3/2, find dy/dx
Step 1: Break them up into 5x/2+3/2
Step 2:dy/dx=5/2 since you bring over 1 and the x is removed since x^1-1=0

 

[floral123]

Re: O'level Maths, Addmaths and Statistics help available he

@ Floral,

given y=5x+3/2, find dy/dx
Step 1: Break them up into 5x/2+3/2
Step 2:dy/dx=5/2 since you bring over 1 and the x is removed since x^1-1=0

thanx but could u tell me what actually "d" means here??
And also the answer is:5/2??

 

[roneyms]

Re: O'level Maths, Addmaths and Statistics help available he

Ehm well d means differentiation?

 

[Anon]

Re: O'level Maths, Addmaths and Statistics help available he

dy/dx means rate of change.

to find dy/dx, we do following:

1. Break the expression to simplest form
2.Reduce power of the variable in equation by one. e.g x^3 would become x^2
3.Any constant in equation becomes zero.

So now we apply these rule to your question:

(5x + 3)/2
= 5x/2 + 3/2 (Making the expression simpler)

As power of x is 1, so 1-1 = 0
When anything have power of zero, the value is 1
So,
5/2 + 0 (Any constant in the expression becomes zero)
5/2 is the answer.

 

[floral123]

Re: O'level Maths, Addmaths and Statistics help available he

dy/dx means rate of change.

to find dy/dx, we do following:

1. Break the expression to simplest form
2.Reduce power of the variable in equation by one. e.g x^3 would become x^2
3.Any constant in equation becomes zero.

So now we apply these rule to your question:

(5x + 3)/2
= 5x/2 + 3/2 (Making the expression simpler)

As power of x is 1, so 1-1 = 0
When anything have power of zero, the value is 1
So,
5/2 + 0 (Any constant in the expression becomes zero)
5/2 is the answer.

thanx alot... :Yahoo!:
plz tell about 2 questions above that!

 

[Anon]

Re: O'level Maths, Addmaths and Statistics help available he

So question is y=(x+3)^2

Now we do the same thing we did before.
But this time we follow the above rule 2 twice
First we would differnciate outside the bracket, than we do it inside the bracket (so twice)

First we reduce the power by 1 and multiply the expression by the original power:
= 2* (x+3)^1
Now we factorise the thing inside the bracket and multiply both of them so:
= (x+3) = 1 (differienciated it !)

now multiplying:
1 * 2(x+3) = 2x+6 ANS

 

[Anon]

Re: O'level Maths, Addmaths and Statistics help available he

Second question is even easiar
x^5 - 3x^2 + 5

I repeat again:
REduce the power by 1 and multiply the term by the original power
Constant become zero

SO:
5* x^4 -2*3x +0
5x^4 -6x Ans

The other question:
x^2 + 3x - 4

2x + 3
= 2x + 3 ANS (Did directly here, try figirin out yourself)

 

[floral123]

Re: O'level Maths, Addmaths and Statistics help available he

Second question is even easiar
x^5 - 3x^2 + 5

I repeat again:
REduce the power by 1 and multiply the term by the original power
Constant become zero

SO:
5* x^4 -2*3x +0
5x^4 -6x Ans

The other question:
x^2 + 3x - 4

2x + 3
= 2x + 3 ANS (Did directly here, try figirin out yourself)

thanks to you.... :Yahoo!:

 

[Anon]

Re: O'level Maths, Addmaths and Statistics help available he

Your Welcome!

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

'd' is the symbol for a very small change. dy/dx refers to change in y with respect to change in x. That is the literal meaning of dy/dx (differentiation with respect to x).

 

[manishr1994]

Re: O'level Maths, Addmaths and Statistics help available he

Im ready to sell all the questions done from the addmaths text book. EVERY single question photocopies. For more info contact me at 0333-3556372

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

People here would do that for free!

 

[xhizors]

Re: O'level Maths, Addmaths and Statistics help available he

lol abcde ur ryt.

 

[Nibz]

Re: O'level Maths, Addmaths and Statistics help available he

I've edited the above post!
Please use correct usernames!

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

@manishr1994: An Addmaths (book) guide is already available in the market, with all the questions solved and explained.