Melody

The pi thing is not included in the special characters.  How weird is that !!

WE are not here to do all your homework for you so you can learn nothing.  I am not anyway.

Why do you post 3 questions that are almost identical. ? I know, ...   because you are a lazy git!

You post just one and then attempt to learn from it and do the others yourself!

What are you finding the surface area of darkKnight?   :)

Yes I can :)

What is -3a^2? (Negative three a squared)

\((-3a)^2=(-3)^2a^2=9a^2\\~\\ -(3a)^2=-3^2a^2=-9a^2\\~\\ -3a^2 \quad \text{can not be simplified}\)

[10,000*1.05^N]+[15,000*1.06^N]+[20,000*1.07^N]+[25,000*1.08^N]=100,000

\([10,000*1.05^N]+[15,000*1.06^N]+[20,000*1.07^N]+[25,000*1.08^N]=100,000\\ [1.05^N]+[1.5*1.06^N]+[2*1.07^N]+[2.5*1.08^N]=10\\\)

Answer from Wolfram|Alpha                Just as guest#1 said. :)

With a calculator ...   

Hi Geno,

It is really good to see you again     

I'll give the explanation a go :)

|3x-1|=|2x+6|

+ and +           3x-1 = 2x+6      (1)

+ and -           3x-1 = - ( 2x+2)    (2) 

- and -           -  (3x-1) = - ( 2x+2)    (3) 

- and +           - (3x-1) = + ( 2x+2)    (4) 

If you look at these 4 options you can see that  

1 and 3 are really the same

and

2 and 4 are really the same.   :)

So there are really only 2 distict options :)

Does that explain it good enough for you?

Hi Tetre :)

\(\dfrac{2027!+2028!}{2028!-2029!}\\ =\dfrac{2027!+2027!*2028}{2028!-2028!*2029}\\ =\dfrac{2027!(1+2028)}{2028!(1-2029)}\\ =\dfrac{2027!(2029)}{2028!(-2028)}\\ =\dfrac{(2029)}{2028(-2028)}\\ =\dfrac{-2029}{2028^2}\\\)

-2029/(2028*2028) = -0.000493339791246