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

Question

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

anonymous · Answer

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

anonymous · Answer

then what would the domain be?

anonymous · Answer

all real numbers?

anonymous · Answer

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

anonymous · Answer

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

anonymous · Answer

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

anonymous · Answer

ah...okay. Thanks guys :)