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41 articles trouvés pour ce sujet.
A limit 2015-02-19
genc pose la question :
Lim (27x^3-1) / (3x-1)
X-> 1/3

Harley Weston lui répond.
A difference quotient 2015-01-12
Sasha pose la question :
Simplify the difference quotient

f(x) − f(a)/ x-a
if x ≠ a.
f(x) = x^3 − 12

Penny Nom lui répond.
Five cubes 2014-01-15
Bob pose la question :
Rick has five cubes. When he arranges them from smallest to largest, the difference between the heights of any two neighbouring cubes is 2 cm. The largest cube is as high as a tower built from the two smallest cubes. How high is a tower built from all five cubes?
Penny Nom lui répond.
Squares and cubes 2013-08-02
Sandra pose la question :
What whole number equals 25 when it is squared and 125 when it is cubed?
Penny Nom lui répond.
a cube-b cube-a+b= ? 2013-06-16
saryu pose la question :
a cube-b cube-a+b= ?
find the answer

Penny Nom lui répond.
Two cubes 2012-09-04
alexis pose la question :
a cube has one face that is equal to the total surface area of another cube. Find the ratio of their volumes
Penny Nom lui répond.
Three metallic cubes 2012-05-13
Pragun pose la question :
Three metallic cubes whose edges are in the ratio 3:4:5 are melt to form a single cube whose diagonal is 12*square root of 3. What are lengths of the edges(in cm) of the three cubes
Penny Nom lui répond.
A pattern is built with cubes. 2011-02-08
e pose la question :
A pattern is built with cubes.
The first item is 1 cube.
The second item is a block of 8 cubes.
The third item is a block of 27 cubes.
If the pattern is continued, how many cubes are needed for the fourth and fifth?

Penny Nom lui répond.
Difference of cubes 2010-05-22
Anad pose la question :
how can we prove a^3 - b^3 is equal to (a-b)(a^2+ab+b^2)?
Penny Nom lui répond.
1^3 + 2^3 + 3^3 +4^3 ... n^3 = ? 2010-01-29
ireimaima pose la question :
Can u please help me with this question.. I find that when i test eg: n=2 for n (n+1) /4, it seems that it does not giving me the right answer of 1^3 + 2^3 = 9 but 3/2... i'm confuse..can u please help me..thanks so much

Prove that: 1^3 + 2^3 + 3^3 +4^3………………………………..n^3 = n (n+1) /4

Penny Nom lui répond.
Cubes and squares 2009-09-16
Stanley pose la question :
What is a three consecutive digit number like 5,6,7 , which is two less than a cube and two more than a square?
Robert Dawson lui répond.
A difference quotient 2009-06-17
Sue pose la question :
When s(x)=x^3+x, compute and simplify the difference quotient s(x+h)-s(x)/h.
Harley Weston lui répond.
Factoring 2008-11-19
Neji pose la question :
How do you factor (y-z) (y+z) (y^4+y^2z^2+z^4) and get (y+z)(y^2-yz+z^2) (y-z) (y^2+yz+z^2) as the answer?
Harley Weston lui répond.
A cubic equation 2008-08-25
RAM pose la question :
The following Cubic Eqn should have three roots - what are they?


Penny Nom lui répond.
Sum and difference of cubes 2008-01-30
Amanda pose la question :
It has been a really long time since I was in Algebra and I can't remember how to factor cubes such as x^3 +81 or subtracting/adding fractions with variables such as [1/(x+h)+2]-[1/x+2]. Please help!!!
Penny Nom lui répond.
Explaining the factoring for the difference of cubes 2008-01-16
Bill pose la question :
A student asked me where did the "difference of cubes" and "sum of cubes" come from. I did not have an answer for her. She is very bright and understands how they work but wanted to know where they derived from. Any help you can offer would be great. Thanks
Stephen La Rocque lui répond.
How many cubes have one face painted red? 2007-11-27
Ashutosh pose la question :
A rectangular block measuring 10 units by 8 units by 6 units is made up of cubes measuring 1 unit on a side. The base of the block is 10 units by 8 units. The outside of the block other than the base is painted red. How many of the unit cubes have exactly one face painted red?
Stephen La Rocque and Penny Nom lui répond.
Cubes 2007-09-21
Yvonne pose la question :
The numbers 756 and 72, expressed as products of prime factors, are 756 = 2² x 3³ x 7 and 72 = 2³ x 3²

Use these result to find,

the smallest integer, x, such that 756x is a perfect cube.

Penny Nom lui répond.
Find all numbers which are both squares and cubes 2007-07-30
Arul pose la question :
what is the easiest way to find the number which is both a square and a cube? the numbers i know are 64 and 729 which is both a sqr and a cube. i took long time to solve this.. is there any easier way?
Steve La Rocque lui répond.
A trillion sugar cubes 2006-11-10
Leeza pose la question :
How many dump trucks (I believe the standard bed size is 16'L x 8'W x 4'D) would it take to hold one trillion sugar cubes (which I believe are approximately 2cm in L, W and D)?
Penny Nom lui répond.
(a^(1/3) – b^(1/3)) ( a^(2/3) + a^(1/3)b^(1/3) + b^(2/3)) 2006-10-24
Julie pose la question :
(a1/3 – b1/3) ( a2/3 + a1/3b1/3 + b2/3)
Haley Ess lui répond.
How many of these cubes have no wax of them? 2006-03-10
Iban pose la question :
cube cheese is 4cm wide, 4cm long, 4cm high. three faces of the cube meet in the corner covers thin layers of wax. The cheese is then cut two, then cut 64 small cubes, which is the length 1cm. How many of these cubes have no wax of them?
Stephen La Rocque lui répond.
Factor 2006-03-08
Brad pose la question :
x3 + 64m3 and 125p3 - q6

Penny Nom lui répond.
3x^4 - 81 2006-01-02
Julio pose la question :
How can I factor the following?:

3x4 - 81

Penny Nom lui répond.
"a" cubed minus "b" cubed 2004-12-02
Denise pose la question :
"a"cubed minus "b"cubed equal (a-b) times
("a"squared plus "ab" plus "b"squared)?

I know this is a formula, but why is it true?

Penny lui répond.
Slicing cubes 2004-11-23
Anthony pose la question :
You are working with a power saw and wish to cut a wooden cube 3-inches on aside into 27 1-inch cubes. You can do this by making six cuts through the cube keeping the pieces together in the cube shape. Can you reduce the number of necessary cuts by rearranging the pieces after each cut?
Chris Fisher lui répond.
Factoring 2004-07-19
A student pose la question :
Factor completely:
3x3 - 24y3
54x6 + 16y3
16xy - 4x - 4y - 1
0.09x2 - 0.16y2

Penny Nom lui répond.
Factoring 2004-04-27
Bipin pose la question :

a to the power of 6 + b to the power of 6

Penny Nom lui répond.
Some factoring problems 2004-04-15
KJ pose la question :

Factor these:
x3+125 -----> (x+5)3
8x3-27 -----> (?)
x2+36 -----> (x+6)2
x4-5x2+4 --> (?)

Penny Nom lui répond.
Factoring 2002-12-11
Larry pose la question :

how do u factor trinonmials

EX: X 3 + Y 3

X 3 - 8Y 3

8X 2 - 72

64A 3 - 125B 6

Penny Nom lui répond.
Factor completely 2002-11-21
Shelley pose la question :
these two questions are to be factored completely but i have no idea how to factor them
  1. (x-4y) 2 - 3(x-4y) - 4
  2. x 6 + y 6

Penny Nom lui répond.
Two cubes 2002-07-12
Vanessa pose la question :
The edges of a cube are 50% as long as the edges of another cube. What percent of the volume of the larger cube is the volume of the smaller cube?
Peny Nom lui répond.
24x^4 + 3x 2002-03-18
gary pose la question :
24x 4 + 3x
Penny Nom lui répond.
The number of hidden cubes 2002-02-05
Katie pose la question :
This problem is about finding the number of cubes visible and hidden in a cube.

In a cube that is 3x3, 19 cubes can be seen. 8 are hidden.
In a cube that is 4x4, 37 cubes can be seen. 27 are hidden.
In a cube that is 5x5, 61 cubes can be seen. 64 are hidden.
In a cube that is 6x6, 91 cubes can be seen. 125 are hidden.

The question is:
Explain how you could find the number of small cubes that are visible and hidden in a cube of any size.

Paul Betts and Penny Nom lui répond.
Some algebra 2001-10-15
James pose la question :
I cannot figure these out I was wondering if you could help me? I have no one to answer my questions.
  1. (7x2 – 3yz)2 – (7x2 + 3yz)2

  2. Use Pascal’s triangle to expand (2x – y)4

  3. 8x3 y - x3 y4

  4. (m + 3n)2 – 144

  5. 12x4 y – 16x3 y2 – 60x2 y3

  6. p3 q2 – 9p3 + 27q2 – 243

Peny Nom lui répond.
The sum of the cubes is the square of the sum 2000-10-10
Otoniel pose la question :
Without using mathematical induction, or any other method discovered after 1010 a.d. , prove that the sum of i3, (where i, is the index of summation) from one to, n, is equal to ((n*(n+1))/2)2
Penny Nom lui répond.
Factoring ^6 2000-01-03
Athena pose la question :

my name is Athena and I have a question on factoring: how would you figure this out:

(x6-y6) and (x6+y6)

Penny Nom lui répond.
towers of cubes 1999-10-05
Sanker pose la question :
I need help to solve this Rules for bulding towers of cubes
rule 1 The number of cubes on the bottom layer is always one less than the number of squares on the grid
rule 2 Each new layer is made with one cube less than the layer underneath it.
  1. Investigate how many different arrangements there are of 4 cubes on top of 5 cubes on a two by three grid

  2. investigate the number of different arrangements of six cubes on top of seven cubes on a two by four grid

  3. investigate the relation between the number of arrangements of cubes and the size of the grid
    • when there are two layers of cubes
    • when there are more than two layers of cubes

Walter Whiteley lui répond.
The sum of the cubes is the square of the sum 1999-08-25
Bernard Yuen pose la question :
How to prove 13 + 23 + 33 + 43 + ... n3 is equal to (1+2+3+...n)2? (for n is positive integer)
Harley Weston lui répond.
Factoring 1999-03-30
Maggie Stephens pose la question :
I don't know anything about factoring would you plese help me.

3x4 - 48

54x6 + 16y3


12x2 - 36x + 27

9 - 81x2

a3 + b3c3

I would greatly appreciate any help you can give me thanks.
Jack LeSage lui répond.

Patterns 1999-01-07
Melis Kalay pose la question :
I'm confused about questions like these:

1. 2by2by2 cube:

If this cube was painted blue on the outside,

  • how many cubes would have 3 blue faces
  • 2 blue faces
  • 1 blue face
  • 0 blue faces

Jack LeSage and Penny Nom lui répond.



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