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mathxyz wrote:

I have deleted the posts in this thread as you have broken our rules by making a personal attack on another member.

I have also removed your signature as I find it equally offensive Any further infringements and you will be banned. Bob

Are you saying that supporting Trump is offensive? In what way is it offensive?

Are you saying that it is offensive to support Trump?

Bob wrote:

Correct

Bob

Beautiful. There's nothing more relaxing for me than to stay home resting on days off. I work out math problems and arrange hymns for classical guitar in the early evening hours. I used to go out on days off. Honestly, the city is just too dangerous to enjoy the park, beach, theatre, etc. I am not exaggerating, Bob. NYC is out of control under democratic leadership.

**mathxyz**- Replies: 1

Give an example to show that sqrt{a^2} is not equal to a. Use it to explain why sqrt{a^2} = | a |.

Phrzby Phil wrote:

So, what did you get and what does the book say?

My answer is [5•cuberoot(2)]/2.

Book's answer is [5cuberoort(4)]/2.

**mathxyz**- Replies: 0

Simplify the expression. Express your answer so that only positive exponents occur. Assume that the variables are positive.

[(16x^2 • y^(-1/3)]^(3/4) divided by [(xy^2)]^(1/4)

After more than 30 minutes with this problem, my answer continues to be (8x^(1/2))/[y^(3/4)].

Book's answer:

(8x^(5/4))/[y^(3/4)]

Bob wrote:

Factorial is only defined for whole numbers. There is a thing called the gamma function. See what wolfram says.

Bob

Ok. Thanks.

Here is what the AI app tells me:

Unfortunately, you can't calculate the factorial of a decimal number like 2.5. Here's why:

* **What's a factorial?** The factorial (represented by the symbol "!") means multiplying a whole number by all the whole numbers less than it down to 1. For example: 5! = 5 * 4 * 3 * 2 * 1 = 120

* **Why not decimals?** Factorials are defined based on the concept of counting and arranging whole objects. You can't have 2.5 objects to arrange, which is why the factorial of a decimal number isn't defined.

Bob wrote:

As both 5 and 8 go into both length and width you can put the tiles either way round and there's no half tiles needed.

Quickest is to use n times area of tile = area of floor.

Bob

Copy. Will do.

Bob wrote:

A shopkeeper buys an item for C it sells it for R.

Their profit is the difference.

Bob

Can you give me a real life example using money? Sorry for the dumb question but I really want to understand this stuff.

Bob wrote:

You can rewrite this as 2 times 2^(2x)

and use logsBob

Copy. Will do.

Bob wrote:

Wolfram agrees.

Bob

Beautiful.

Bob wrote:

Yes.

Bob

Perfect. Not too bad.

Bob wrote:

Yes; do it twice so the denominator = 2

Bob

I did that but my answer is not the book's answer. Can you work it out for me?

Bob wrote:

The inconsistency shows I've performed an illegal act so that suggests I cannot cancel as that's really division by zero. That leads to the possibility that x=0. Then check it fits. Anything^0 =1 so LHS = RHS = 0. It works.

Bob

Copy. Moving on....

Bob wrote:

Have to. I'd start by using logs

Bob

Using longs? How?

**mathxyz**- Replies: 2

I know that, for example, 3! = 3 x 2 x 1 or 6.

What happens when we take the factorial of a decimal number?

Show how to compute the value of (2.5)!

**mathxyz**- Replies: 2

How many tiles of length 5 cm and breadth 8 cm are needed to tile the floor of a bed room 200 cm long and 400 cm wide?

Seeking the set up only.

Thanks.

**mathxyz**- Replies: 2

Find x.

2^(2)^(2)^(2) = 4^(x)

Let me see.

2^[(2)^(2)] = 2^(4) = 16.

I now have 2^(16) = 4^(x).

Let 4^(x) = 2^(2)

2^(16) = 2^(2x)

Same base on both sides means to equate powers.

16 = 2x

16/2 = x

8 = x

You say?

**mathxyz**- Replies: 2

The profit equation is given as

P = R - C, where P is profit, R is revenue and C is cost.

I really don't understand much about business mathematics.

Can someone explain what the profit equation actually means and how to use it by providing a real life word problem?

**mathxyz**- Replies: 2

Find x.

4^(x) + 4^(x) = 1

How is this done?

P. S. I continue my self-study of college algebra with Sullivan on paper and will post from the book when I get stuck.

**mathxyz**- Replies: 2

What is 6^(6)^(6) ÷ 10?

Let me see.

Note: 6^(6) = 46656.

I now have 6^(46656) ÷ 10.

Using a calculator, I get this:

6^(46656) = 2.65911977215 x 10^(36305).

[2.65911977215 x 10^(36305)]/10

I get 2.65911977215 x 10^(36304).

You say?

**mathxyz**- Replies: 2

The product of three consecutive positive odd integers divided by their sum is equal to 95. What are these three numbers?

Let n, n + 2, and n + 4 be the three consecutive odd integers.

Let me see.

[(n(n + 2)(n + 4)]/[n + n + 2 + n + 4] = 95

Is this the correct set up?

Phrzby Phil wrote:

What do you need to multiple the denominator by so that it is an integer? Multiple the numerator by the same.

I will write cuberoot(2) as 2^(1/3).

Do you mean to multiply the top and bottom by 2^(1/3)?

Bob wrote:

If 1 is the zero row and 1 1 the first row and 1 2 1 the second row then the formula is

where n is the row number and r the (r+1) th element.

So put n=20 and r = 6

Bob

If you ask me nicely on Wednesday I'll show you the proof (by induction).

Ok. Looks easy to do. Thanks.

Bob wrote:

You know that list I told you to keep. Well it's easy to just check. Or start with the squares and add 8.

Bob

I guess there's no getting away from making a list.