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2 years ago

Javier simplified the expression below. Find and describe the three mistakes he made.

Mathematics

2 answers:

Lilit [14]2 years ago

8 0

Answer:

1.Javier did not write the coefficient raised to power of 3

2.Javier wrote $x^4$ instead of $x^3$

3.Javier did divide exponents instead of subtraction of exponents

Step-by-step explanation:

We are given that Javier simplified the expression

$(\frac{20x}{5x^8})^{-3}$

We have to find three mistakes made by Javier.

$(\frac{20x}{5x^8})^{-3}$

$\frac{(20x)^{-3}}{(5x^8)^{-3}}$

$\frac{(5x^8)^3}{(20x)^3}$

By using property; $a^{-x}=\frac{1}{a^x}$

$\frac{125x^{24}}{8000x^3}$

By using property: $(ab)^x=a^xb^x$

$(a^x)^y=a^{xy}$

$\frac{1}{64}x^{24-3}$

By using property $\frac{a^x}{a^y}=a^{x-y}$

$\frac{1}{64}x^{21}$

Javier made three mistakes are given below:

1.Javier did not write the coefficient raised to power of 3

2.Javier wrote $x^4$ instead of $x^3$

3.Javier did divide exponents instead of subtraction of exponents.

Irina18 [472]2 years ago

7 0

Which of the following did you include in your response?

Javier did not raise the coefficients to the third power

When Javier raised (x^1)^3 to the third power, he wrote that x^4, but it equals x^3.

In the last step, Javier divided the exponents. He should have used the quotient of powers property and subtracted them.

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Here is the link to the spreadsheet with standard deviation calculation:
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