I have a question regarding some steps in a solution

[mendem03]

Question 1
step 1
=(2^n-1)/2^n + 1/2^(n+1)
step 2
=2(2^n-1)/2^(n+1) + 1/2^(n+1)
step 3
=2^(n +1)-2+1/2^(n+1)
I don't know how steps 2 and 3 where achieved
can someone please help me

 

[mathman]

Step 2 is simply 1/2ⁿ = 2/2ⁿ⁺¹.

Step 3 doesn't look right. Could you clarify the expression?

 

[HallsofIvy]

It would help if you told us what the problem is that this is supposed to be the solution to!

 

[mendem03]

2^(n +1) -2+1 / 2^(n+1)
this just means that: 2 to the power of (n+1) -2+1 divided by 2 to the power of (n+1)
the next step is
2^(n +1) -1 / 2^(n+1)

 

[mathman]

2 to the power of (n+1) -2+1

You need to put in parentheses. It is not clear what -2 and +1 relate to.