Question

Suppose we have the radical function, f(x)=(7-∜(3x+1))/5
What is the domain of f?
Compute f(5)-5

Answer 1

f(5) = [7 - (3(5) + 1) ^(1/4) ] -5
f(5) = [7 - 2]/ 5
f(5) = 5/5 = 1

Thus, f(5) - 5 = -4

Answer 2

then what would the domain be?

Answer 3

all real numbers?

Answer 4

domain you have so solve
\[3x+1\geq 0\]
\[3x\geq -1\]
\[ x\geq -\frac{1}{3}\]

Answer 5

I thought that the domain was suppose to be the numbers that don't make the denominator 0...

Answer 6

when you take an even root of a negative number, you get a nonreal result. Therefore; when you take an even root, any x that makes the radicand negative is excluded from the domain

Answer 7

ah...okay. Thanks guys :)