query 2

See my notes.

You should therefore always include a detailed self-critique when your solution doesn't completely agree with the given solution. Without the self-critique I can't tell what you did and did not understand about the solution and I have no way of helping you address things you might not understand.

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20:06:12 query R.2.46 (was R.2.36) Evaluate for x = -2, and y = 3 the expression (2x - 3) / y and explan how you got your result.

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RESPONSE --> 2x-3/y= 2(-2)-3/3 = -4-3/3=-7/3

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20:09:08 query R.2. 55 (was R.2.45) Evaluate for x = 3 and y = -2: | |4x| - |5y| | and explan how you got your result.

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RESPONSE --> I I4xI - I5yI I= I4x - 5yI= I-1yI= 1y

This doesn't agree with the given solution and should have been self-critiqued.

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21:32:18 query R.2.64 (was R.2.54) Explain what values, if any, must not be present in the domain of the expression (-9x^2 - x + 1) / (x^3 + x)

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RESPONSE --> -9x^2 - x+1/x^3+x= -9*x*x-x+1/x*x*x+x=

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06:04:51 ** The denominator of this expression cannot be zero, since division by zero is undefined.

Since x^3 + x factors into (x^2 + 1) ( x ) we see that x^3 + x = 0 only if x^2 + 1 = 0 or x = 0.

Since x^2 cannot be negative x^2 + 1 cannot be 0, so x = 0 is indeed the only value for which x^3 + x = 0. **

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RESPONSE --> I am still a little confused by this problem, but I will continue working it and re-working it until I am able to solve it on my own.

In a good self-critique you need identify the specific things you do and do not understand in the given solution, and either demonstrate your understanding or ask specific questions about what you don’t understand. That way, once you have defined your difficulties I can help you address them.

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06:08:15 query R.2.73 (was R.4.6). What is (-4)^-2 and how did you use the laws of exponents to get your result?

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RESPONSE --> (-4)^2= (-4)(-4)= 16

The operation of ""raising to a power"" is performed before any other operation.

Again your solution did not agree with the given solution and should have been self-critiqued.

(-4)^(-2) = 1 / (-4)^2 = 1 / 16.

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06:14:30 query Extra Problem. What is (3^-2 * 5^3) / (3^2 * 5) and how did you use the laws of exponents to get your result?

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RESPONSE --> I must be having 'user' problems again...I am not sure which equation is being described right now.

Extra Problem:

(3^2*5^3)/(3^2*5)=

((3)(3)*(5)(5)(5))/((3)(3)*5)=

(9*125)/(9*5)=

1125/45= 225/9

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