Answer:
(ab)/9
Step-by-step explanation:
The product of a and b is written ...
ab
Division by 9 is indicated by a fraction with 9 in the denominator and the dividend in the numerator. In text form, it looks like ...
(ab)/9
In typeset form it looks like ...
[tex]\dfrac{(ab)}{9}[/tex]
The parentheses are necessary in both cases if you want to make sure the product is formed before the division occurs. The Order of Operations requires that the contents of parentheses be evaluated first.
On the other hand, in text form, ab/9 is supposed to be evaluated left to right, so the multiplication should occur before the division. (There is no "left to right" for the typeset fraction in the case where there are no parentheses.)
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Comment on the question
Technically speaking, There is no way to write the expression so that the multiplication is required before the division, because the associative and commutative properties of multiplication allow the sequence to be rearranged to any convenient order.