Evaluate (1/4)^(-1): Converting Negative Exponents to Reciprocals

Question

(14)1 (\frac{1}{4})^{-1}

Video Solution

Solution Steps

00:04 Let's simplify this together.
00:07 We're using a formula for negative exponents.
00:11 If a fraction, A over B, has a negative exponent, negative M,
00:16 we take the reciprocal, B over A, and use a positive exponent, M.
00:22 Let's try this technique in our exercise.
00:25 We'll switch to the reciprocal and change the exponent to positive.
00:30 Remember, any number to the power of one is just that number.
00:34 And that's how we solve the problem!

Step-by-Step Solution

We use the power property for a negative exponent:

an=1an a^{-n}=\frac{1}{a^n} We will write the fraction in parentheses as a negative power with the help of the previously mentioned power:

14=141=41 \frac{1}{4}=\frac{1}{4^1}=4^{-1} We return to the problem, where we obtained:

(14)1=(41)1 \big(\frac{1}{4}\big)^{-1}=(4^{-1})^{-1} We continue and use the power property of an exponent raised to another exponent:

(am)n=amn (a^m)^n=a^{m\cdot n} And we apply it in the problem:

(41)1=411=41=4 (4^{-1})^{-1}=4^{-1\cdot-1}=4^1=4 Therefore, the correct answer is option d.

Answer

4 4