Using rational approximations, what is an inequality statement comparing √21 and √17? Enter <, >, or =.

1 answer

To compare 21 and 17 using rational approximations, let's first find approximate values for both square roots.

  1. 21:

    • We know that 42=16 and 52=25, so 21 is between 4 and 5.
    • A more precise approximation can be obtained by estimating: 4.52=20.25(too low) 4.62=21.16(too high)
    • Thus, 214.58.
  2. 17:

    • Similarly, since 42=16 and 52=25, 17 is also between 4 and 5.
    • A more precise approximation: 4.12=16.81(too low) 4.22=17.64(too high)
    • So, 174.12.

Now, we compare the two approximations:

214.58and174.12

Since 4.58>4.12, we conclude:

21>17

Therefore, the inequality statement comparing 21 and 17 is:

21>17

In the required format, the answer is:

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