Hey guys,
Nice work on the answer here - I'd also like to use this question to bring up a pretty huge strategic point for working with exponents.
MULTIPLY
Almost all of the exponent rules that we know are related to multiplication/division, so when you're dealing with an exponent problem with addition/subtraction, there's an extremely high likelihood that you'll need to factor out a common term to turn that operation into multiplication. If I sound repetitive right now, it's only because just about every day there's a tough exponent problem posted on this board that can be solved through multiplication!
I love Rahul's method above - factoring the common 3^x leaves 1+1+1, so you have 3 * 3^x. Then you can use one of the other major exponent rules at our disposal - when multiplying exponentials with common bases, you add the exponents, and this one turns into 3^(x+1).
When performing calculations with exponents, find a way to multiply and you'll have your entire complement of exponent rules available to you.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
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