1,000,000 Question Thread :D

[Juddinator]

Simplification can be done now.

Your lightning fast lol!

Speed are precision are essential.

Of course! How silly of me! Thanks TT and kenhung123

[Ilovemathsmeth]

Simplification can be done now.

Your lightning fast lol!

Practice will make you like this. Don't worry, you'll be like this soon!

[Juddinator]

With the number set {x:|x-1|less that or equal to 4}, I cannot figure out the interval notation.

Essentials is useless at this explanation lol

[kenhung123]

x-1 <= 4
x<= 5

or

x-1>4
x>5

Thats just my guess

[TrueTears]

With the number set {x:|x-1|less that or equal to 4}, I cannot figure out the interval notation.

Essentials is useless at this explanation lol

Sigh... I swear Essentials does the shittest job of explaining modulus..

[kyzoo]

With the number set {x:|x-1|less that or equal to 4}, I cannot figure out the interval notation.

Essentials is useless at this explanation lol

Sigh... I swear Essentials does the shittest job of explaining modulus..

Nuu don't bag my precious Essentials =X

[Juddinator]

Sigh... I swear Essentials does the shittest job of explaining modulus..
[/quote]
Yes, yes it does!

[stonecold]

What exercise was this modulus question Juddy?

[kat148]

What exercise was this modulus question Juddy?

Example 11c of Chapter 1D I think.

[Juddinator]

Yes it is! Sorry I've been away from the computer all day doing the last minute Christmas rush!

They don't even do the example well!    How annoying

[kyzoo]

Sigh... I swear Essentials does the shittest job of explaining modulus..

Yes, yes it does!
[/quote]

Hmm, I will partially retract my statement.


y = |f(x)| is easy to understand, you just ensure the graph never goes under the x-axis

y = f(|x|) the book doesn't explain well, so I had to conceive my own method of understanding it

To get the graph of y = f(|x|), first sketch the graph of y = f(x) for x > 0, or the entire "right page" of the graph. Then reflect the drawn section about the y-axis, or "flip the page and imprint it into the left page."

[superflya]

i know this questions stupid but majorly cbf thinking tonight

1a) rewrite Tan^2 x in terms of sinx and cosx ( i can do this bit)
1b) simplify the expression into 2 parts using sin^2x + cos^2x=1

[Lighties]

so

And then expand to

[Juddinator]

Q1) An aircraft flies from its base to locate a fire at an unknown distance, x km away. It travels straight to the fire and back, averaging 240km/h for the outward trip and 320km/h for the return trip. If the plane was away for 35 minutes, find the distance, x km.

I tried using simultaneous equations to do this but I got stuck :\

Q2) Water flows into a tank at a rate of 15 litres per minute. At the beginning the tank contained 250L.
a) Write an expression for the volume, V litres, of water in the tank at the time t minutes.
b) How many litres of water are there in the tank after an hour?
c) The tank has a capacity of 5000L. How long does it take to fill?

I know I can do part b and c as long as I have a formula, but I am having trouble constructing one.

Thanks!

[Stroodle]

For the first one:



For the second one:

a)

b)

c)