1. ## few sample problems

1.
A B

Max surface area covered by 4 Max surface area covered by 1 place mat with

2. [] = absolute value

A B

[a+b+c] [a]+[b]+[c]

3.

4-1/x = 4x

I thought I did this one right but for some reason my answer is not coming out right.

Thanks for the help everyone!!!!!!!  Reply With Quote

2. i apologize for question 1. It is supposed to be separated. 4 place mats radius r and 1 place mat radius 2r. Sorry  Reply With Quote

3. hey , am just beginner in math , but i have an idea about third question

what was your answer , 3/4 , or what , here is how this come with me

4-1 4x
___ = ___

x 1

then we can use multiplying method and yield 4x = 4-1 then 3/4

maybe am wrong , you have to search more  Reply With Quote

4. .2. [] = absolute value

A B

[a+b+c] [a]+[b]+[c]

column B is greater. Because [a]+[b]+[c] always makes a positive number  Reply With Quote

5. 2. Ans D.(can not be determined)

Ex.
trail-1 : a =1 b=2 c=3 (A=B)
trail:2 : a=-1 b=-2 c=-3(A=B)
Trail:3 a=1 b=2 c=-3 (A<B)

3.
4-(1/x)= 4x
4x-1 =4x^2
=> 4x^2-4x+1=0
=> (2x-1)^2=0
(2x-1)=0
x=1/2  Reply With Quote

6. Question 1:

4 mats of radius 1 would cover 4 x (pi x 1squared) = 4pi

1 mat of radius 2 would cover 1 x (pi x 2squared) = 4pi

Try it with r=3
4 x (pi x 3squared) = 36pi
1 x (pi x 6squared) = 36pi

Try it with r=1/2
4 x (pi x 1/2squared) = 1pi
1 x (pi x 1squared) = 1pi

The key here is that you're always taking 4 x (the square of the radius) and comparing it to (2 x radius)squared.
Factor (2 x radius)squared = 2squared x radius squared, and since 4 = 2squared, they're going to be the same always.  Reply With Quote