Why Do Exponential Rules Affect Equations Like -(y^2-1)^(1/2) = (1-y^2)^(1/2)?

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In summary, the conversation discusses an equation, -(y^2-1)^(1/2)= (1-y^2)^(1/2), and the speaker is unsure why it must be true. They request an explanation using rules of exponentials and mention similar equations with integer powers. The speaker also shares their intuition about the sign of the expression in brackets, but acknowledges the need for a proper explanation. The conversation ends with a question about the source of the equation and a suggestion to substitute y=0 to demonstrate that the equations are not equal.
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Jumpsmash
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I have come across in the solution to a question. -(y^2-1)^(1/2)= (1-y^2)^(1/2). However I do not know why this has to be the case, and would appreciate anyone showing me, presumably using rules of exponentials, how this could be shown to be true. Similarly if the power is not fractional but either a positive or negative integer. ie. -(ax-b)^2= (b-ax)^2 or -(ax-b)^3= -(b-ax)^3

With regard to the last two, thinking about it I have an intuitive sense that if the power is even then this will make whatever is in the bracket +ve and if if it is odd then if whatever in the bracket will still be negative. But this is not really much good, and, as I say, I'd like to know how to show these to be the case.
 
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Where did you see that? Try substituting y=0 into both and you will see that they are not equal
 

What are the basic rules of exponentials?

The basic rules of exponentials are:

  • Product Rule: when multiplying two exponential expressions with the same base, add the exponents
  • Quotient Rule: when dividing two exponential expressions with the same base, subtract the exponents
  • Power Rule: when raising an exponential expression to a power, multiply the exponents
  • Zero Rule: any number raised to the 0th power is equal to 1
  • Negative Rule: any number raised to a negative power is equal to 1 divided by that number raised to the positive power

How do I simplify exponential expressions?

To simplify exponential expressions, you can use the basic rules of exponentials to combine like terms and reduce the expression to its simplest form. You can also use the properties of logarithms to rewrite the expression in a different form.

What is the difference between exponential and logarithmic functions?

Exponential functions involve a base number raised to a variable exponent, while logarithmic functions involve a base number raised to a certain power to equal the variable. In other words, exponential functions ask "what power do I need to raise this number to get this result?" while logarithmic functions ask "what number do I need to raise this base to get this result?"

Can I graph exponential functions?

Yes, exponential functions can be graphed. Their graphs have a characteristic shape, with a steep incline or decline as the x-values increase, depending on the base number. The graphs also have a horizontal asymptote, which is a line that the curve approaches but never touches.

How are exponential functions used in real life?

Exponential functions can be used to model growth or decay in various real-life scenarios, such as population growth, compound interest, radioactive decay, and bacterial growth. They are also commonly used in economics and finance to analyze trends and make predictions.

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