Melody

$$h^2=a^2+b^2$$

Thanks Geno,

I'm just giving another example.

Say you have 5 b***s that are lettered as A,B,C, D and E

how many ways can you choose 3 or them

Let me see

ABC    ABD    ABE    ACD    ACE    ADE

BCD    BCE    BDE

CDE

that is 10 ways.  (assuming that I didn't double up or miss any)

5C3 is just this.   It is how many ways you can select 3 things out of 5 things so it must equal 10

check  

I'll enter    nCr(5,2)    into the web 2 calc.  :)

$${\left({\frac{{\mathtt{5}}{!}}{{\mathtt{3}}{!}{\mathtt{\,\times\,}}({\mathtt{5}}{\mathtt{\,-\,}}{\mathtt{3}}){!}}}\right)} = {\mathtt{10}}$$

Oh and if you are doing it ny hand the calc just showed  you the formula :)

Nice work Chris, I had to think for a bit about that first integral, it is not one that I have memorized :/

There is no answer because there is no equal sign and you have not asked us to do anything else with it either.

You can use the quadratic formula but the number under the square root is negative (-39) so there will be no real solutions :)

Thanks anon - that is exactly correct :)

I do it differently  - I just wanted to check that we get the same answer.  :)

I am expanding across the top row. :)

1(-1--2)-0+1(0--2) = 1+2=3

I have no idea how you did that Chris but I have seen some strange stuff like that in video clips before I think. :)

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Sorry, I meant square feet and I was thinking it was 48 sq feet.  Wrong one 2 counts.

I will try that again.

2 in = 0.0508 m

No not quite.

infinty+infinity=infinity

Why are you using pi - there are no circles here.  It is not a cone!

Volume of a square pyramid

$$\\V=\frac{1}{3}*l^2*h\\\\
1024=\frac{1}{3}*l^2*12\\\\
1024=4*l^2\\\\
256=l^2\\\\
l=16inches$$