Help with maths homework!

[Brigadier]

Decades since I did this sort of stuff, and I'm clearly not any help to him in this rusty state.

A (line-by-line?) walk-through of the following would be much appreciated - as I can't figure out how to type superscript numbers, I've resorted to ^ instead.


"Simplify 3x^2(2xy + 6x^3y^2)"

I got stumped right at the start (the 3x^2(2xy bit); is it

6x^3y,

6x^3 + 3xy,

or something completely different?

Or should I be solving the bit inside the brackets first?


TIA

 

[Gerrydelasel]

Expand:
3x^2(2xy + 6x^3y^2)
= 3x^2 * 2xy + 3x^2 * 6x^3 y^2
= 6x^2 * xy + 18x^2 * x^3 y^2
= 6x^3 * y + 18x^5 * y^2

You could now take out 6x^3 * y as a common factor, if you want, although whether that is 'simpler' is open to discussion.

 

[EFLImpudence]

3x² * 6x³
=18x^5

 

[Gerrydelasel]

3x² * 6x³
=18x^5

Oops, thanks for spotting! Corrected.

 

[Brigadier]

3x² * 6x³
=18x^5

Thanks EFLI, but I don't know where your example came from.
Is it "the answer", or illustrative?

 

[Gerrydelasel]

Thanks EFLI, but I don't know where your example came from.
Is it "the answer", or illustrative?

I made an error in my expansion - I wrote 12 instead of 18. That's what ELFI was correcting. I've fixed it.

 

[Brigadier]

Gotcha

 

[Himaginn]

Brig, next time you want help with your homework, the characters that you need are under the ohm (Ω) sign at the top of the space where you type your message, as illustrated below:
characters like:
4° 5×6 ±3÷1²×3³≠¼√½

 

[Himaginn]

And the strikethrough is two to the left under 'insert'. Or just use ]S] ]/S]. I've intentionally put the first of each bracket the wrong way round so it doesn't invoke the strikethrough.
tertretret
If you use the BB code editing button (far right top corner of the typing area) you will see the codes in your message.
You can revert back to normal by clicking on 'Rich Text Editor' below, which you'll only see if you're in Rich Text Editor mode.

 

[Brigadier]

Brig, next time you want help with your homework, the characters that you need are under the ohm (Ω) sign at the top of the space where you type your message, as illustrated below:
characters like:
4° 5×6 ±3÷1²×3³≠¼√½

View attachment 94964

I did look last night H, but they didn't leap out.........either I missed them, or they might be missing in Linux.

 

[EFLImpudence]

the characters that you need are under the ohm (Ω) sign

Is there a way to make any character superscript?

E.g. my 'to the power 5' is not there nor in the windows character map.

 

[Himaginn]

the characters that you need are under the ohm (Ω) sign

Is there a way to make any character superscript?

E.g. my 'to the power 5' is not there nor in the windows character map.

Not that I know of, even if you do it in Word, it don't paste across.
Although the Word shortcut works for ALT+0179 = ³ and ALT+0178 = ²

 

[Himaginn]

BTW the ALT+0185 works here as well = ¹. even though it's not in the list.

 

[Himaginn]

Here is a list of available BB codes: http://forums.codeguru.com/misc.php?do=bbcode but the availability is set by Admin.
Obviously the [sup]12345[/sup] isn't available, nor is the [sub]12345[/sub] whereas others are:

• 
  5
  5
  etc

If you use the BB code editor you'll see the codes.
But I've just written them in as normal when typing.
Perhaps if we ask Admin nicely they'll make the [sup] and [sub] available.

 

[Himaginn]

And the strikethrough is two to the left under 'insert'. Or just use ]S] ]/S]. I've intentionally put the first of each bracket the wrong way round so it doesn't invoke the strikethrough.
tertretret
If you use the BB code editing button (far right top corner of the typing area) you will see the codes in your message.
You can revert back to normal by clicking on 'Rich Text Editor' below, which you'll only see if you're in Rich Text Editor mode.

I've found a way of illustrating the code without it being invoked:

• [list]
  [*][b]bold[/b]
  [*][s]strikthrough[/s]
  [*][u]underline[/u]
  [*][i]italic[/i]
  [*][color=red]etc[/color]
  [*][code]stops the code working]/code]
  [*]the asterisks are the bullet point markers
  [*][/list]