evaluate the exponential function at the specified value of x

f(x)=4

^{x}, x= -4-
CREATE FREE ACCOUNT
- Access thousands of free resources from expert tutors
- Comment on posts and interact with the authors
- Ask questions and get free answers from tutors
- View videos, take interactive quizzes, and more!

- Become a Student
- Become a Student
- Sign In

evaluate the exponential function at the specified value of x

f(x)=4^{x}, x= -4

Tutors, please sign in to answer this question.

Hey Carlos

You need to think about the rules for exponents. Is there any that tells you how to deal with negative exponents?

Here is a way to think about it. For positive exponents you could write x^n = x*x^(n-1), as long as n is greater than 0. This can be rewritten as: x^(n-1) = (x^n)/x, as long as x is not 0. Now suppose n is 0, and the rule gives us: x^(-1) = x^(0)/x. Since x^0 is 1, this means x^(-1) = 1/x. If we assume this holds as long as n is an integer(positive or negative) and x is not 0, then we have that x^(-2) = x^(-1)/x = ([x^0]/x)/x =(1/x)/x = 1/x^2, and in general x^(-n) = 1/(x^n). Then in your case, 4^(-4) = 1/(4^4).

From here just multiply to find: 1/(4*4*4*4)=?

Hope this is helpful,

Jose

f(x) = 4^{x}

f(x=4) = 4^{4} = 4*4*4*4 = ??

Katelyn D.

Engaging, Patient, and Flexible Instruction

Monmouth Junction, NJ

5.0
(47 ratings)

Wesley L.

Premier MIT Math Tutor and SHSAT/SAT/ACT Specialist

New York, NY

5.0
(124 ratings)

Ronniel M.

Making Math Easy- SAT Prep, Algebra, Precalculus, English, Spanish

Newark, NJ

5.0
(86 ratings)

## Comments