Final answer:
The corrected expression x0.9x0.9x0.9 simplifies to x2.7. In division of exponentials, subtract the exponents with the same base, and in scientific notation, adjust the decimal point to express large or small numbers in a more manageable form.
Step-by-step explanation:
The expression x .9.9.9 appears to be a typo, but assuming it is meant to represent repeated multiplication of exponents, let's correct it to x0.9x0.9x0.9. To simplify this, you would add the exponents since they have the same base. Therefore, the expression becomes x2.7.
When dividing exponentials with the same base, you subtract the exponents. For example, if you divide 106 by 103, you subtract the exponents, resulting in 10(6-3) which simplifies to 103. In scientific notation, if we were to divide 1.9436 by 1000, we would adjust the decimal point three places to the left, leading to 0.0019436, and express it as 1.9436 x 10-3.