Q. If g(x)= 3x+√x, what is the value of g(d^2+6d+9)
Ans. Can I solve this way?
d^2+6d+9= (d+3)(d+3)= d= -3
g(-3)= 3(-3)+√-3= -9-√3.
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Compound Functions
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You can't, because you don't know that d² + 6d + 9 = 0. You could, however, say that
g(d² + 6d + 9)
= 3(d² + 6d + 9) + √(d² + 6d + 9)
= 3d² + 18d + 27 + √(d² + 6d + 9)
But we'd need more info from here.
g(d² + 6d + 9)
= 3(d² + 6d + 9) + √(d² + 6d + 9)
= 3d² + 18d + 27 + √(d² + 6d + 9)
But we'd need more info from here.
