• Jun 6th 2012, 07:44 AM
JesseElFantasma
Hi, all!
I have exams coming up soon and I'm just going through my textbook and practising a few past exam papers and I have this which I need help on. :)

a) 2(-3a2b)2

b) 2bn x 23bThanks in advance!!!!!
(Smile)
• Jun 6th 2012, 08:00 AM
Reckoner
Quote:

Originally Posted by JesseElFantasma
a) 2(-3a2b)2

b) 2bn x 23
(Smile)

It would be helpful to know what you want to do with these expressions. Are you being asked to simplify them? If so, apply the following properties of exponents:

$\displaystyle a^ma^n = a^{m+n}$

$\displaystyle \frac{a^m}{a^n} = a^{m-n}$

$\displaystyle (ab)^n = a^nb^n$

$\displaystyle \left(\frac ab\right)^n = \frac{a^n}{b^n}$
• Jun 6th 2012, 08:10 AM
Sarasij
a) 2(-3a2b)2=2 x (-3)2 x (a2)2 x (b)2 = 2 x 9 x a4 x b2 = 18a4b2

b)2bn x 23b = 2 x 23 x bn x b = 24 x bn+1 = 16bn+1

anyways I would always say to practice these sorts of exercises with the formulas that Reckoner gave here.
• Jun 6th 2012, 08:14 AM
Wilmer
Quote:

Originally Posted by JesseElFantasma
b) 2bn x 23bThanks in advance!!!!!

Is the "x" a multiplication sign? If so, use "*" in the future?
Or did you mean a "+"; or "-" ?
• Jul 27th 2012, 12:39 PM
davidthompson873