f(x) = -x + 23
g(x) = 2x - 7
We need to find the value of x for which f(x) = g(x), therefore:

Therefore, x = 10
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f(n) = n³ + 1
Where:
n ∈ Z ; n > 0
We need to find the first four terms, so:
f(1) = 1³ + 1 = 2
f(2) = 2³ + 1 = 8 + 1 = 9
f(3) = 3³ + 1 = 27 + 1 = 28
f(4) = 4³ + 1 = 64 + 1 = 65
Therefore, the first four terms are:
2 , 9 , 28 , 65