SOLUTION: Suppose that f(x) = ax + b, where a and b are real numbers. Given that f(f(f(x))) = 8x + 21, what is the value of a + b?

SOLUTION: Suppose that f(x) = ax + b, where a and b are real numbers. Given that f(f(f(x))) = 8x + 21, what is the value of a + b?

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Question 257618: Suppose that f(x) = ax + b, where a and b are real numbers.
Given that f(f(f(x))) = 8x + 21, what is the value of a + b?
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Hint: Starting with , plug in for 'x' to get . Do so again to get . Now simplify to get . From here, just equate the two expressions and solve for 'a' and 'b'.
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