Mathematics Homework Help
Grand Canyon University Logarithms & Identity Functions Questions
Provide screenshots or explanations of how you solved the problems.
1. This DQ is dealing with the composition operator of functions. That is, performing one function and then immediately using that output as the input to another possible different function. Here is my problem:
f(x) = 4x + 3
g(x) = sqrt(4 – x2)
to compute (f o g)(x) (which is read as “f of g of x”, the circle in the middle is the composition operator (like a + sign but for composition)). I would write:
f(g(x)) = f( sqrt(4 – x2)) = 4( sqrt(4 – x2)) + 3
then there is no more algebra to simplify.
for (g o f)(x) which is the other way around we have:
g(f(x)) = g(4x+3) = sqrt(4-(4x+3)2) = sqrt(4 – 16×2 – 24x – 9) = sqrt(-5- 16×2 – 24x)
then there is no more algebra to simplify.
Some things to discuss possibly:
1. If a function f composed with itself gives the identity function (i.e f(f(x)) = x) then what can we say about f?
2. On an unrelated note, do you think mathematics is discovered or invented? Is there a difference between the words?
NThis DQ switches over to logarithms: https://en.wikipedia.org/wiki/Logarithm which is NOT an algorithm: https://en.wikipedia.org/wiki/Algorithm
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Here are some interesting real world applications: https://betterexplained.com/articles/using-logs-in-the-real-world
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some discussion point
1. why would the logathim at 0 not have a defined value