Question

5. Evaluate the following without finding the actual
cubes.
(i) 11^3-10^3​

Answer 1

Answer:

331.

Explanation:

$we \: know \: that \\ {a}^{3} - {b}^{3 \: } = (a - b)( {a}^{2} + ab \: + {b}^{2} ) \\ so \\ puttig \: a = 11 \: and \: b = 10 \\ we \: have \\ {11}^{3} - {10}^{3} = \: (11 - 10)( {11}^{2} + 11 \times 10 + {10}^{2} ) \\ = \: 1 \times (121 + 110 + 100) \\ = 331$

Answer 2

Answer:

Answer:

331

Explanation:

we know that

a-=(a - b)(a + ab +)

SO

puttig a = 11 and b = 10

we have

11- 10 = (11 - 10)(11 +11 x 10+ 10

= 1x (121 + 110 +100)

= 331