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## #1 Help Me ! » Derivatives » 2006-08-21 23:50:30

Titus
Replies: 2

I can't work out the derivative for this equation;

P = 2t³/3 + t² - 40t - 5

and then i need to find what 't' is when the derivative of the above equation = 0.

Any help would be great.
Thanks!

## #2 Help Me ! » More questions! » 2006-05-02 21:20:54

Titus
Replies: 1

Can anyone help me on these please?

(5x³/y^4) X (y^5/10x^4)

(3a²/b³) X 6ab

(4x)³ ÷ (4x)²

2x³ ÷ (2x)²

thanks

Titus
Replies: 1

Really need some help with my maths homework, any help would be greatly appreciated

by the way "-²" is to the power of negative 2, same deal with negative 3.
^ is just to the power of.

These ones have to go to positive indicies, thats all:
(c-²)/4

(3x^-1 y-²)/z²

(x-³)/(3^-1)

(P^½)-½

(2x-³)³

thanks

## #4 Help Me ! » Quadratics Again.. » 2006-02-25 23:41:39

Titus
Replies: 3

If a quadratic line passes through (1,-2) and (2,-14)

what is the line that satisfies this information?

are there any others that satisfy this? how many?

thanks

## #5 Help Me ! » Quadratic Functions » 2006-02-25 19:58:44

Titus
Replies: 4

I have this question which asks;

--

A family of quadratic functions just touches the x-axis at the point (3,0). Find the family of quadratic functions.

--

What exactly is a family of quadratic equations and how do i find it?

Also, how would i go about finding one particular function from the family?

Thankyou.

## #6 Help Me ! » Perpendicular Lines » 2006-02-13 19:58:23

Titus
Replies: 3

From the equation 3y = 5 - x

how do you find the gradient? and what is it?

thanks

## #7 Help Me ! » Hep with Trig. please :) » 2005-08-22 23:44:53

Titus
Replies: 9

The structure below measures 10m in length by 0.8m in width. In total, there are 21 diagonal pieces exactly like AB and two extra pieces- CD. Pieces CD are parallel to pieces AB. Pieces AB are inclined at 60 degrees from the horizontal.

After that i need to find the total length of the out frame and all 21 pieces of AB.

Any help is greatly appreciated.

Note: the vertical lines (apart from those on the outer frame) are not a part of the actual structure. They are merely usaed to form triangles so certain lengths can be calculated.

thanks.

## #8 Help Me ! » Problem Solving » 2005-03-29 18:53:15

Titus
Replies: 8

lets say for example;

I want to make a non-cylindrical water tank which much have a volume of 6m cubed, from a single sheet of metal.

This sheet of metal has an area of 6m squared, but it's too small to make the tank. why is that?

## #9 Re: Help Me ! » generalizations help! » 2005-03-07 18:26:26

MathsIsFun wrote:

I may have to change my answer after thinking, but here is my "gut feel":

An even number is, by definition, able to be divided evenly by 2. So any whole number multiple of an even number (the multiple could be odd or even) must also be able to be divided evenly by 2.

In algebra it may go something like this:

A number "x" is even if x=2n, where n is an integer

And a number "y" is odd if y=2m+1, where m is an integer

So, multiplying any "x" and "y" gives: xy=2n(2m+1)

But we know the definition of even is 2 times an integer ...

So, if n(2m+1) is an integer (we may need to prove that ), then 2n(2m+1) will be even, and xy must be even.

thanks so much for that!
just one more thing on that, do we just assume that 2n(2m+1) is even, or is this because by using the 2 before the brakctes, we are saying everything is mulitplied by 2 and therefor even?