Final answer:
To find the prime decomposition of 136 as 2^a x b, we repeatedly divide by 2 to get 2^3 x 17, which yields a = 3 and b = 17.
Step-by-step explanation:
When Etta writes down the prime decomposition of 136 as 2a x b, to calculate the values of a and b, we must first find all the prime factors of 136. Since 136 is an even number, we can continuously divide by 2 (which is the smallest prime number) until we can no longer do so. Let's perform the decomposition step by step:
- 136 ÷ 2 = 68
- 68 ÷ 2 = 34
- 34 ÷ 2 = 17
Now, we have reached 17, which is a prime number and cannot be divided further by 2. So we have divided by 2 a total of 3 times (23), and we are left with the prime number 17. Hence, we can write the prime decomposition of 136 as 23 x 17, which gives us a = 3 and b = 17.