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Expert: Sherman D. - 9/7/2005


Question
if f(x)= x+5 and g(x)= x^2-3, find the following:

1) f(g(0))
2) f(f(-5))
3) g(g(x))


Answer
Let me know if you got my answer, because i accidentally clicked Sorry i couldn't answer the question even though i can.

f(x) = x + 5
g(x) = x^2 - 3

1.)
f(g(0))
g(0) = (0)^2 - 3 = 0 - 3 = -3

Now you have

f(-3) = -3 + 5 = 2

so f(g(0)) = 2

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2.)
f(f(-5))
f(-5) = -5 + 5 = 0
f(0) = 0 + 5 = 5

so f(f(-5)) = 5

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3.)
g(g(x))
g(x) = x^2 - 3
g(x^2 - 3) = (x^2 - 3)^2 - 3
g(x^2 - 3) = ((x^2 - 3)(x^2 - 3)) - 3
g(x^2 - 3) = (x^4 - 3x^2 - 3x^2 + 9) - 3
g(x^2 - 3) = x^4 - 6x^2 + 9 - 3
g(x^2 - 3) = x^4 - 6x^2 + 6

so g(g(x)) = x^4 - 6x^2 + 6

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Sherman D.

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I can answer questions dealing in mathematics of all kinds except for Physics and Calculus, but i can answer questions in Pre-Calculus and Chemistry. I can also answer questions in Recipes of all kinds. I can find games cheats/walkthroughs, but i can`t find a specific game online or offline. I can also do history and recipes for alcoholic beverages.

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Mathematics, Recipes, History, and Games.

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High School graduated. I graduated with honors, and i was in Beta Club for a year and a half.

Awards and Honors
Principle's list and A and B honor roll in high school only.

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