Question

Evaluate 2n -1, where n=7
Options 1,64,127

Answer 1

127

Explanation:

We are given the expression:

(2^n)-1

We also know that n=7. Therefore, we can substitute 7 in for n.

(2^7)-1

Evaluate the exponent first. 2^7 is equal to multiplying 2, 7 times.

2^7=2*2*2*2*2*2*2=128

2^7=128

128-1

Subtract 1 from 128

127

Answer 2

127

Explanation:

n = 7

`2^n - 1 =`

`= 2^7 - 1`

`= 128 - 1`

`= 127`