Simplify the expression. Write the answer with positive exponents. Assume all variables represent nonzero real numbers.

[tex]\[
\left(-5 a^9\right)\left(2 a^5 b^{-3}\right) = \square
\][/tex]



Answer :

Sure! Let's simplify the given mathematical expression step-by-step. The expression to simplify is:

[tex]\[ (-5a^9)(2a^5b^{-3}) \][/tex]

1. Separate the constants, and then the variables with the same base:
[tex]\[ (-5) \cdot (2) \cdot (a^9) \cdot (a^5) \cdot (b^{-3}) \][/tex]

2. Multiply the constants:
[tex]\[ -5 \times 2 = -10 \][/tex]

3. Combine the terms with the same base:
- For the [tex]\(a\)[/tex] terms: [tex]\(a^9 \cdot a^5\)[/tex]
- For the [tex]\(b\)[/tex] term: not applicable here since there is only [tex]\(b^{-3}\)[/tex]

Using the properties of exponents, specifically [tex]\(x^m \cdot x^n = x^{m+n}\)[/tex]:

[tex]\[ a^9 \cdot a^5 = a^{9+5} = a^{14} \][/tex]

4. Keep the [tex]\(b\)[/tex] term as it is with the exponent unchanged:
[tex]\[ b^{-3} \][/tex]

5. Combine all simplified terms:
[tex]\[ -10 \cdot a^{14} \cdot b^{-3} \][/tex]

The final simplified expression is:

[tex]\[ -10a^{14}b^{-3} \][/tex]

Since the problem asks for the answer with positive exponents only, we need to convert [tex]\(b^{-3}\)[/tex] to its positive exponent counterpart:

Using the property [tex]\(x^{-n} = \frac{1}{x^n}\)[/tex]:

[tex]\[ b^{-3} = \frac{1}{b^3} \][/tex]

So the expression [tex]\(-10a^{14}b^{-3}\)[/tex] can be rewritten as:

[tex]\[ -10a^{14}\frac{1}{b^3} = \frac{-10a^{14}}{b^3} \][/tex]

Thus, the simplified expression with positive exponents is:

[tex]\[ \boxed{\frac{-10a^{14}}{b^3}} \][/tex]