k is a positive number. If k is twice its reciprocal, and j is twice k, then jk =

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k is a positive number. If k is twice its reciprocal, and j is twice k, then jk =

by BTGmoderatorLU » Sun Apr 18, 2021 8:00 am

00:00

A

B

C

D

E

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Source: Magoosh

k is a positive number. If k is twice its reciprocal, and j is twice k, then jk =

A. $$2\sqrt{2}$$
B. $$4$$
C. $$4\sqrt{2}$$
D. $$8$$
E. $$8\sqrt{2}$$

The OA is B

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Re: k is a positive number. If k is twice its reciprocal, and j is twice k, then jk =

by [email protected] » Thu Jul 15, 2021 9:05 am
BTGmoderatorLU wrote:
Sun Apr 18, 2021 8:00 am
Source: Magoosh

k is a positive number. If k is twice its reciprocal, and j is twice k, then jk =

A. $$2\sqrt{2}$$
B. $$4$$
C. $$4\sqrt{2}$$
D. $$8$$
E. $$8\sqrt{2}$$

The OA is B
Solution:

If k is a positive number, then its reciprocal is 1/k. Let’s determine the value of k:

k = 2 * 1/k

k^2 = 2

k = ±√2

Since k is positive, k = √2. Since j is twice k, j = 2√2 and so jk = 2√2 * √2 = 4.