Question 881821
the worksheets at the bottom show the calculations.

number 1 shows r(s).
number 2 shows r(-s).
number 3 shows r(s^2).


number 4 shows the calculations involved in the simplification of r(s) + r(-s).
the result of that simplification is shown just abov4e number 5.
you are basically putting the r(s) + r(-s) under a common denominator so you can add them together.
number 4a shows the multiplications involved in getting to the common denominator.
number 4b shows the results of those multiplications.
number 4c shows the result of placing the fractions under a common denominator.
number 4d further simplifies by performing the indicted operations.
number 4e shows the final result.


number 5 is basically dividing the simplified version of r(s) + r(-s) by 2 to get the final result of r(s) + r(-s) divided by 2.


as can be seen in number 5 r(s) + r(-s) divided by 2 is the same as r(s^2) which was shown in number 3.

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