You can't 'solve' it.

There is no equal sign!

Mon 27/10/14

1) This one looks really interesting.  Thanks Chris and anonymous.

@@ End of Day Wrap          Sun 26/10/14           Sydney, Australia            Time 9:50pm      ♬

Hello everybody,

Fantastic answers today from Geno3141, Kitty<3 and Alan.

I just pulled a few interest questions:

1) Vectors.   Thanks Alan

$$\\LHS\\
=(cis60)^{1991}+(cis(-60))^{1991}+1\\
=(e^{60i})^{1991}+(e^{-60i})^{1991}+1\\
=(e^{60*1991*i})+(e^{-60*{1991}*i})+1\\
=(cos(60*1991)+isin(60*1991))+(cos(-60*1991)+isin(-60*1991))+1\\
Now\;\; cos(-\theta)=cos(\theta)\;\;and\;\;sin(-\theta)=-sin(\theta)\\
so\\
=cos(60*1991)+cos(-60*1991)+isin(60*1991)+isin(-60*1991)+1\\
=cos(60*1991)+cos(-60*1991)+i[sin(60*1991)+sin(-60*1991)]+1\\
=cos(60*1991)+cos(60*1991)+i[sin(60*1991)-sin(60*1991)]+1\\
=2cos(60*1991)+i[0]+1\\
=2cos(60*1991)+1\\
=2cos(60*[6*331+5])+1\\
=2cos(60*6*331+60*5])+1\\
=2cos(360*331+60*5)+1\\
=2cos(60*5)+1\\
=2cos(300)+1\\
=2\times\frac{1}{2}+1\\
=1+1\\$$

$$\\=2\\
\ne 1\\
$The equation is not true$$$

So I agree with Alan's answer.    

Alan's answer is here.

Thank you very much Alan.

I whited the question because it was repeated on the next page (this page) and also I had re-thought my question.

Gino has answered here

I don't understand the question

What is 

4*exp(-5x^2)

It increases the area by x^2  Alan.

sorry

I was thinking it increases the area by x^2 units squared.

but

you have interpreted it as x units squared.

Your interpretion is probably the intended one.   

Original rectangle  L*W = A

New rectangle   (L-1)*(W+1) = A + x

L*W + L - W - 1 = A + x

or L - W - 1 = x   since L*W = A

If x has to be a positive integer as well then:

When L-W = 2 units,  x = 1 square unit

If x doesn't have to be an integer then there it has no smallest value (it can be infinitesimally small). 

.

how do i apply the above method to solve this wuestion is all i need please for now.

Rewrite as:

(204-203) + (202-201) + ... + (6-5) + (4-3) + (2-1) 

      1        +       1       + ... +    1    +    1    +   1

There are 102 terms so the sum is 102.

.

Good thinking Geno :)

Do you mean   $$25^2=625$$

or

$$5^2=25$$

x  can be anything because these are not equations.  There are no equal signs  

2/100*8,000,000,000

Are you the anon who asked the question?  What don't you understand?

$$-(\frac{-1}{2})^3\\\\
=-\frac{(-1)^3}{(2)^3}\\\\
=-\frac{-1}{8}\\\\
=\frac{1}{8}\\\\$$

Try looking through this

27/10/14

LOOKS INTERESTING

If you think about and understand this you will see that the cos(angle) is given by the x value on the unit circle.  2pi is one complete revolution.  The x value at 0 radians is 1

3pi=3pi-2pi=pi radians on the unit circle. The x value at pi on the unit circle is -1

I hope that helps.    

Thanks anon tht is a good answer except you need a negative sign.

a pos times by a neg = a neg

-22

Or the acos function on the site calc on the home page.

This is latex notation Gino it means

$$-3\le x < 7$$

To get this I just opened up the LaTex formula tab and pasted it in. :)

(the back slash means it is a function, the le means less than or equal to )

The answer is 

[-3,7)

The square bracket meants that the -3 is included and the round bracket means that the 7 is not included.

mmm... sweet pie- oh, thanks