How to factor out s and distribute the power of 6

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umzung
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Homework Statement
How does one bracket become the other?
Relevant Equations
See the attempt at a solution.
How does
Screenshot 2019-11-26 22.17.43.png
become
Screenshot 2019-11-26 22.17.54.png
?

I can see the s has been factored out and the power of 6 distributed, but how do we know this happens, short of multiplying out the brackets?
 
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First factor the s in the top expression. Then what happens with the power 6? I think it will be clearer then.
 
umzung said:
Homework Statement: How does one bracket become the other?
Homework Equations: See the attempt at a solution.

How does View attachment 253352become View attachment 253353?

I can see the s has been factored out and the power of 6 distributed, but how do we know this happens, short of multiplying out the brackets?
Just factor the expression inside the parentheses.
##\frac 1 2 s + \frac 1 2 s^2 = s( \frac 1 2 + \frac 1 2 s)##.

Then use the property that ##(ab)^n = a^nb^n##
 
Mark44 said:
Just factor the expression inside the parentheses.
##\frac 1 2 s + \frac 1 2 s^2 = s( \frac 1 2 + \frac 1 2 s)##.

Then use the property that ##(ab)^n = a^nb^n##
That's clearer, thanks.
 
I would actually go a little further than that. [tex]\frac{1}{2}s+ \frac{1}{2}s^2= \frac{1}{2}s(1+ s)[/tex] so that [tex]\left(\frac{1}{2}s+ \frac{1}{2}s^2\right)^6= \frac{1}{64}s^6(1+ s)^6[/tex].