Question

阿巴阿巴

鵝⋯我有點搞不懂了⋯
（圖一我寫的圖二書上的）
乘除的有效位數不是取最小的有效位數嗎？
那以｜（19.70-20.03）/20.03｜來看，不就是四位有效數字除以四位有效數字，答案不是應該等於0.01647？所以worst-case precision不是應該等於0.98352？為什麼書上寫0.984😭
我要被這個東西搞瘋了天啊

ex 1-4
-選最差項
19,70-20.03
= 1 -
=0.9835
Xn
20,03
worst-case precision: 1- | Xn-Xn
Xn=
X = 20,10+20.00+20.20+ 19.80 + 19,70 + 20.00+20,30 +20.10.
8
=20.03.

CHAPTER 1 INTRODUCTION TO INSTRUMENTATION
The average output, determined by adding the output values and dividing by
eight, is equal to 20.02 degrees. The fifth reading differs from the average by
the greatest amount; therefore, the worst-case precision is related to and
found from this reading.
X-X
擇最差項
Precision 1 -
又
|19.70-20.02|
=1.
|=1-0.016=0.984
(1-5)
20.02

Answer 1

qn

分子先算
加減完並取絕對值是 0.33
只剩兩位有效數字

然後再做除法，只取兩位是 0.016