If P(x) = 4+2\sqrt{x+2} and G(x) = 4-8x, then what is the largest constant a such that P(G(a)) is defined?
P ( G(x)) = 4 + 2 / sqrt [ 4-8x + 2] = 4 + 2 /sqrt [ 6 - 8x]
6 - 8x ≥ 0
6 ≥ 8x
x ≤ 6/8
x ≤ 3/4
Then
a ≤ 3/4
