Question

Evaluate 9.9 whole cube

Answer 1

Hey!

___________

(9.9)^3

(9 + 0.9)^3

Using identity -

( a + b )^3 = a^3 + b^3 + 3ab (a + b)

Now, a = 9 , b = 0.9

(9)^3 + (0.9)^3 + 3 × 9 × 0.9 ( 9 + 0.9)

= 729 + 0.729 + 24.3 ( 9.9 )

= 729 + 0.729 + 240.57

= 970.299

___________

Hope it helps...!!!

Answer 2

Heya !!

Here's your answer.. ⬇⬇
______________________________

$= {(9.9)}^{3} \\ \\ = {(100 - 90.1)}^{3} \\ \\ = {(100)}^{3} - {(90.1)}^{3} \\ \\ using \: \: identity \: \: \\ {(a - b)}^{3} = {(a)}^{3} - {(b)}^{3} - 3ab(a - b) \\ \\ = {(100)}^{3} - {(90.1)}^{3} - 3(100)(90.1)(100 - 90.1) \\ \\ = 1000000 - 731432.70 - 3(9010)(9.9) \\ \\ = 268567.29 - 27030(9.9) \\ \\ = 268567.29 - 267597 \\ \\ = 970.29$
_______________________________

Hope it helps..

Thanks :)