Use the identify for the DIFFERENCE OF TWO SQUARES:stephny wrote:(2^3-1)(2^3+1)(2^6+1)(2^12+1)
(a-b)(a+b) = a²-b².
(2³-1)(2³+1)(2�+1)(2¹²+1)
= (2�-1)(2�+1)(2¹²+1)
= (2¹²-1)(2¹²+1)
= 2²�-1.
algebra
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(a-b)(a+b) = a²-b².
(2³-1)(2³+1)(2�+1)(2¹²+1)
= (2�-1)(2�+1)(2¹²+1)
= (2¹²-1)(2¹²+1)
= 2²�-1.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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Hi stephny,
Mitch has showcased one of the hidden Algebra patterns that you could see on Test Day: Classic Quadratics. If you find yourself looking at a question and thinking "it will take forever to do all of this math", then there's likely to be a more elegant/faster way of solving the problem.
Another thing to consider is that you would have 5 answer choices to look at (which you did not provide); the formatting of the answer choices might give you an idea of what the "pattern" is behind the question. They might also give you a way to quickly estimate (and eliminate) answers since they're either too big, too small, or simply not possible.
GMAT assassins aren't born, they're made,
Rich
Mitch has showcased one of the hidden Algebra patterns that you could see on Test Day: Classic Quadratics. If you find yourself looking at a question and thinking "it will take forever to do all of this math", then there's likely to be a more elegant/faster way of solving the problem.
Another thing to consider is that you would have 5 answer choices to look at (which you did not provide); the formatting of the answer choices might give you an idea of what the "pattern" is behind the question. They might also give you a way to quickly estimate (and eliminate) answers since they're either too big, too small, or simply not possible.
GMAT assassins aren't born, they're made,
Rich
