Exponentiation
When we think of zy^x, z is the coefficient, y is the base and x is the exponent. The exponent is the number of times the base of something is multiplied by itself.
2² = 2 × 2 = 4
2⁴ = 2 × 2 × 2 × 2 = 16
In terms of multiplying and dividing, these are generally done in the same way as we have seen over the course of this book. Here is an example:
2³ × 2⁴ = (2 × 2 × 2) × (2 × 2 × 2 × 2)
= 8 × 16
= 128
= 16 / 8
= 2
Additionally, 2^(3+4) = 2^7 = 2 × 2 × 2 × 2 × 2 × 2 × 2
= (2 × 2 × 2) × (2 × 2 × 2 × 2) = 2³ × 2⁴.
So remember that:
A^(m+n) = A^m × A^n
Sometimes, you may have to raise your exponent to another exponent, but this can easily be done as well:
(4²)³ = (4 × 4)³
16³ = 16 × 16 × 16
= 4096
You might also see negative exponents on the test. To calculate a negative exponent, take the reciprocal of the base and then change the sign of the exponent.
2^(-4) = (1/2)⁴
This can then be further reduced to:
That is about all there is to know about calculating the power of something. You won't find many questions like these on the GMAT, but you'll see a few so be sure you know how to do them.
More Practice from the GMAT® Review 13th Edition: Questions 65, 106, 111, 117, 122