Question

EXERCISE 7.1
1. Which of the following numbers are not perfect cubes?
(1) 216
(ii) 128
(iii) 1000
(V) 46656
(iv) 100​

Answer 1

$\large 128$ and $\large 100$ are not perfect cubes.

Test: $\large \sqrt[3]{ 216 } = 6$

$\large \sqrt[3]{ 128 } = 4\sqrt[3]{2}\approx 5.0396842$

$\large \sqrt[3]{1000} = 10$

$\large \sqrt[3]{ 46656 } = 36$

$\large \sqrt[3]{ 100 } = 4.6415...$

Answer 2

Answer:

$128 and \large 100100 are not perfect cubes.</p><p></p><p>Test: \large \sqrt[3]{ 216 } = 63216=6</p><p></p><p>\large \sqrt[3]{ 128 } = 4\sqrt[3]{2}\approx 5.03968423128=432≈5.0396842</p><p></p><p>\large \sqrt[3]{1000} = 1031000=10</p><p></p><p>\large \sqrt[3]{ 46656 } = 36346656=36</p><p></p><p>\large \sqrt[3]{ 100 } = 4.6415...3100=4.6415...</p><p></p><p>$